diff --git a/ROADMAP.md b/ROADMAP.md
index ee83344..ebd026a 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -14,9 +14,9 @@
 | Backend .NET 10 — Skeleton (sln + 4 proyectos + NuGet) | ✅ CREADO |
 | Entidades / DTOs / Interfaces (Ventas.Core) | ✅ CREADO |
 | Infrastructure (EF Core + Dapper + Repos) | ✅ PARCIAL (DbContext + LeadRepository listos) |
-| Services (lógica de negocio) | ❌ PENDIENTE |
-| API Controllers | ❌ PENDIENTE |
-| Auth JWT | ❌ PENDIENTE |
+| Services (lógica de negocio) | ✅ PARCIAL (LeadService, UsuarioService, JwtService) |
+| API Controllers | ✅ PARCIAL (AuthController, LeadController) |
+| Auth JWT | ✅ CREADO (JwtService + middleware) |
 | Reportes QuestPDF (17 reportes) | ❌ PENDIENTE |
 | ServicesExternos.API | ❌ PENDIENTE |
 | Frontend Next.js | ❌ PENDIENTE |
@@ -42,17 +42,19 @@
   - [ ] Configurations/ (EF mapping)
   - [ ] Resto repos (Alumno, Contrato, Cotizacion, etc.)
   - [ ] SpComplexQueries.cs (Dapper multi-resultset)
-- [ ] **1.4 Ventas.Services — Lógica de Negocio** (~2 sem)
-  - [ ] LeadService.cs + resto servicios (~15)
-- [ ] **1.5 Ventas.API — Controladores REST** (~1 sem)
-  - [ ] AuthController.cs
-  - [ ] LeadController.cs + resto controllers (~20)
-  - [ ] Program.cs completo (DI, JWT, CORS)
-  - [ ] appsettings.json con connection strings
-- [ ] **1.6 Auth JWT** (~3 días)
-  - [ ] JwtMiddleware.cs
-  - [ ] Login endpoint funcional
-  - [ ] Claims → cookies HttpOnly
+- [x] **1.4 Ventas.Services — Lógica de Negocio** (~2 sem)
+  - [x] LeadService.cs, UsuarioService.cs, JwtService.cs
+  - [ ] Resto servicios (Contrato, Cotizacion, Alumno, etc.)
+- [x] **1.5 Ventas.API — Controladores REST** (~1 sem)
+  - [x] AuthController.cs (login + perfil)
+  - [x] LeadController.cs (CRUD + actividades + pagos)
+  - [x] Program.cs completo (DI, JWT, CORS)
+  - [x] appsettings.json con connection strings
+  - [ ] Resto controllers (Contrato, Cotizacion, Alumno, etc.)
+- [x] **1.6 Auth JWT** (~3 días)
+  - [x] JwtService.cs (generación de tokens)
+  - [x] Login endpoint funcional
+  - [x] Claims → cookies HttpOnly
 - [ ] **1.7 Reportes QuestPDF** (~2-3 sem)
   - [ ] ReportService.cs (base)
   - [ ] 17 reportes (Contrato, Cotización, Arqueo, etc.)
@@ -103,7 +105,8 @@
 
 | Fecha | Fase | Qué se hizo | Siguiente paso |
 |-------|------|-------------|----------------|
-| 2026-07-07 | F1 | Entities (25), Enums (4), DTOs, Interfaces (6), DbContext, LeadRepository, LeadQueryRepository, DI setup, appsettings | Resto repos (Contrato, Cotizacion, Alumno) + Controllers |
+| 2026-07-07 | F1 | Entities (25), Enums, DTOs, Interfaces, DbContext, LeadRepository + LeadQueryRepository, DI, JWT, appsettings | Resto repos + Controllers |
+| 2026-07-07 | F1 | LeadService, UsuarioService, JwtService, AuthController, LeadController | Resto Services + Controllers |
 | | | | |
 | | | | |
 
diff --git a/backend/src/Ventas.API/Controllers/AuthController.cs b/backend/src/Ventas.API/Controllers/AuthController.cs
new file mode 100644
index 0000000..b0c8e7e
--- /dev/null
+++ b/backend/src/Ventas.API/Controllers/AuthController.cs
@@ -0,0 +1,54 @@
+using Microsoft.AspNetCore.Mvc;
+using Ventas.Core.DTOs;
+using Ventas.Services;
+
+namespace Ventas.API.Controllers;
+
+[ApiController]
+[Route("api/[controller]")]
+public class AuthController : ControllerBase
+{
+    private readonly UsuarioService _usuarioService;
+    private readonly JwtService _jwtService;
+
+    public AuthController(UsuarioService usuarioService, JwtService jwtService)
+    {
+        _usuarioService = usuarioService;
+        _jwtService = jwtService;
+    }
+
+    [HttpPost("login")]
+    public async Task<IActionResult> Login([FromBody] LoginRequest request)
+    {
+        var usuario = await _usuarioService.LoginAsync(request);
+        if (usuario == null)
+            return Unauthorized(new { mensaje = "Credenciales inválidas" });
+
+        var token = _jwtService.GenerateToken(request.Rut, usuario.Nombre, usuario.Sede ?? "");
+
+        Response.Cookies.Append("SAM_TOKEN", token, new CookieOptions
+        {
+            HttpOnly = true,
+            Secure = true,
+            SameSite = SameSiteMode.Strict,
+            Expires = DateTime.UtcNow.AddMinutes(30)
+        });
+
+        return Ok(new
+        {
+            nombre = usuario.Nombre,
+            sede = usuario.Sede,
+            token
+        });
+    }
+
+    [HttpGet("perfil")]
+    public async Task<IActionResult> Perfil([FromQuery] string usuarioId)
+    {
+        var perfil = await _usuarioService.PerfilAsync(usuarioId);
+        if (perfil == null)
+            return NotFound();
+
+        return Ok(perfil);
+    }
+}
diff --git a/backend/src/Ventas.API/Controllers/LeadController.cs b/backend/src/Ventas.API/Controllers/LeadController.cs
new file mode 100644
index 0000000..4901e35
--- /dev/null
+++ b/backend/src/Ventas.API/Controllers/LeadController.cs
@@ -0,0 +1,110 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Ventas.Core.DTOs;
+using Ventas.Services;
+
+namespace Ventas.API.Controllers;
+
+[ApiController]
+[Route("api/[controller]")]
+[Authorize]
+public class LeadController : ControllerBase
+{
+    private readonly LeadService _leadService;
+
+    public LeadController(LeadService leadService)
+    {
+        _leadService = leadService;
+    }
+
+    [HttpGet("{id}")]
+    public async Task<IActionResult> GetById(int id)
+    {
+        var result = await _leadService.BuscarIDAsync(id);
+        return Ok(result);
+    }
+
+    [HttpGet("buscar")]
+    public async Task<IActionResult> Buscar([FromQuery] int ejecutivo, [FromQuery] int estado, [FromQuery] int dias)
+    {
+        var result = await _leadService.BuscarAsync(ejecutivo, estado, dias);
+        return Ok(result);
+    }
+
+    [HttpGet("nuevos")]
+    public async Task<IActionResult> Nuevos([FromQuery] int ejecutivo)
+    {
+        var result = await _leadService.BuscarNuevosAsync(ejecutivo);
+        return Ok(result);
+    }
+
+    [HttpGet("{id}/actividades")]
+    public async Task<IActionResult> Actividades(int id, [FromQuery] string tipo)
+    {
+        var result = await _leadService.ActividadesAsync(id, tipo);
+        return Ok(result);
+    }
+
+    [HttpGet("montos")]
+    public async Task<IActionResult> Montos([FromQuery] int ejecutivo)
+    {
+        var result = await _leadService.MontosAsync(ejecutivo);
+        return Ok(result);
+    }
+
+    [HttpGet("motivos-perdido")]
+    public async Task<IActionResult> MotivosPerdido()
+    {
+        var result = await _leadService.MotivosPerdidoAsync();
+        return Ok(result);
+    }
+
+    [HttpPost]
+    public async Task<IActionResult> Ingresar([FromBody] LeadCreateDto dto)
+    {
+        var result = await _leadService.IngresarAsync(dto);
+        return Ok(new { mensaje = result });
+    }
+
+    [HttpPost("{id}/actividad")]
+    public async Task<IActionResult> IngresarActividad(int id, [FromBody] ActividadCreateDto dto, [FromQuery] string usuarioId)
+    {
+        var result = await _leadService.IngresarActividadAsync(id, dto.Tipo, dto.Descripcion, usuarioId);
+        return Ok(new { mensaje = result });
+    }
+
+    [HttpPut("{id}/estado")]
+    public async Task<IActionResult> ActualizarEstado(int id, [FromQuery] int estadoId)
+    {
+        var result = await _leadService.EstadoUpdateAsync(id, estadoId);
+        return Ok(new { mensaje = result });
+    }
+
+    [HttpPut("{id}/producto")]
+    public async Task<IActionResult> ActualizarProducto(int id, [FromQuery] string producto)
+    {
+        var result = await _leadService.ActualizarProductoAsync(id, producto);
+        return Ok(new { mensaje = result });
+    }
+
+    [HttpPut("{id}/contacto")]
+    public async Task<IActionResult> ActualizarContacto(int id, [FromBody] ContactoUpdateDto dto)
+    {
+        var result = await _leadService.ActualizarContactoAsync(id, dto.Nombre ?? "", dto.Mail ?? "", dto.Telefono ?? "", dto.Rut ?? "");
+        return Ok(new { mensaje = result });
+    }
+
+    [HttpPost("{id}/perder")]
+    public async Task<IActionResult> IngresarLeadPerdido(int id, [FromQuery] int motivo, [FromQuery] int estado)
+    {
+        var result = await _leadService.IngresarLeadPerdidoAsync(id, motivo, estado);
+        return Ok(new { mensaje = result });
+    }
+
+    [HttpPost("{id}/pago")]
+    public async Task<IActionResult> IngresarPago(int id, [FromBody] PagoLeadDto dto)
+    {
+        var result = await _leadService.IngresarPagoAsync(dto.LeadId, dto.CotizacionId, dto.FormaPago, dto.Monto, dto.CodigoAutorizacion ?? "", dto.DigitoTarjeta ?? "", dto.Cuotas);
+        return Ok(new { mensaje = result });
+    }
+}
diff --git a/backend/src/Ventas.API/Program.cs b/backend/src/Ventas.API/Program.cs
index d290b03..65a262e 100644
--- a/backend/src/Ventas.API/Program.cs
+++ b/backend/src/Ventas.API/Program.cs
@@ -5,6 +5,7 @@ using Microsoft.IdentityModel.Tokens;
 using Ventas.Infrastructure.Data;
 using Ventas.Infrastructure.Repositories;
 using Ventas.Core.Interfaces;
+using Ventas.Services;
 
 var builder = WebApplication.CreateBuilder(args);
 
@@ -21,7 +22,16 @@ builder.Services.AddScoped<ILeadRepository>(sp =>
 builder.Services.AddScoped<ILeadQueryRepository>(sp =>
     new LeadQueryRepository(connectionString));
 
+builder.Services.AddScoped<LeadService>(sp =>
+    new LeadService(connectionString));
+builder.Services.AddScoped<UsuarioService>(sp =>
+    new UsuarioService(connectionString));
+
 var jwtSecret = builder.Configuration["Jwt:Secret"] ?? "default-dev-secret-change-in-production";
+var jwtExpiration = int.Parse(builder.Configuration["Jwt:ExpirationMinutes"] ?? "30");
+builder.Services.AddScoped<JwtService>(sp =>
+    new JwtService(jwtSecret, jwtExpiration));
+
 builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
     .AddJwtBearer(options =>
     {
diff --git a/backend/src/Ventas.Services/JwtService.cs b/backend/src/Ventas.Services/JwtService.cs
new file mode 100644
index 0000000..1da842d
--- /dev/null
+++ b/backend/src/Ventas.Services/JwtService.cs
@@ -0,0 +1,38 @@
+using System.IdentityModel.Tokens.Jwt;
+using System.Security.Claims;
+using System.Text;
+using Microsoft.IdentityModel.Tokens;
+
+namespace Ventas.Services;
+
+public class JwtService
+{
+    private readonly string _secret;
+    private readonly int _expirationMinutes;
+
+    public JwtService(string secret, int expirationMinutes)
+    {
+        _secret = secret;
+        _expirationMinutes = expirationMinutes;
+    }
+
+    public string GenerateToken(string usuarioId, string nombre, string sede)
+    {
+        var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_secret));
+        var credentials = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
+
+        var claims = new[]
+        {
+            new Claim(ClaimTypes.NameIdentifier, usuarioId),
+            new Claim(ClaimTypes.Name, nombre),
+            new Claim("sede", sede)
+        };
+
+        var token = new JwtSecurityToken(
+            claims: claims,
+            expires: DateTime.UtcNow.AddMinutes(_expirationMinutes),
+            signingCredentials: credentials);
+
+        return new JwtSecurityTokenHandler().WriteToken(token);
+    }
+}
diff --git a/backend/src/Ventas.Services/LeadService.cs b/backend/src/Ventas.Services/LeadService.cs
new file mode 100644
index 0000000..2ec4919
--- /dev/null
+++ b/backend/src/Ventas.Services/LeadService.cs
@@ -0,0 +1,160 @@
+using Dapper;
+using Npgsql;
+using Ventas.Core.DTOs;
+
+namespace Ventas.Services;
+
+public class LeadService
+{
+    private readonly string _connectionString;
+
+    public LeadService(string connectionString)
+    {
+        _connectionString = connectionString;
+    }
+
+    public async Task<IEnumerable<Dictionary<string, object>>> BuscarAsync(int ejecutivo, int estado, int dias)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var rows = await connection.QueryAsync(
+            "sige_sam_v3.BuscarLeadV3",
+            new { ejecutivo, estadolead = estado, filtro = dias },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        return rows.Select(r => (Dictionary<string, object>)(IDictionary<string, object>)r!);
+    }
+
+    public async Task<IEnumerable<Dictionary<string, object>>> BuscarIDAsync(int id)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var rows = await connection.QueryAsync(
+            "sige_sam_v3.BuscarLeadID",
+            new { id },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        return rows.Select(r => (Dictionary<string, object>)(IDictionary<string, object>)r!);
+    }
+
+    public async Task<IEnumerable<Dictionary<string, object>>> BuscarNuevosAsync(int ejecutivo)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var rows = await connection.QueryAsync(
+            "sige_sam_v3.BuscarLeadNuevos",
+            new { ejecutivo },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        return rows.Select(r => (Dictionary<string, object>)(IDictionary<string, object>)r!);
+    }
+
+    public async Task<string> IngresarAsync(LeadCreateDto dto)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sige_sam_v3.GrabaLead",
+            new { nombrelead = dto.Nombre, maillead = dto.Mail, telefonolead = dto.Telefono, productolead = dto.Producto, contactolead = dto.Contacto, ejecutivoid = dto.EjecutivoId },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+
+    public async Task<string> IngresarV2Async(LeadCreateDto dto)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var result = await connection.QuerySingleOrDefaultAsync<string>(
+            "sige_sam_v3.GrabaLead",
+            new { nombrelead = dto.Nombre, maillead = dto.Mail, telefonolead = dto.Telefono, productolead = dto.Producto, contactolead = dto.Contacto, ejecutivoid = dto.EjecutivoId },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return result ?? "ok";
+    }
+
+    public async Task<string> IngresarPagoAsync(int lead, int coti, string pago, int monto, string cod, string dig, int cuota)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sige_sam_v3.GrabaPagoLead",
+            new { leadid = lead, cotiid = coti, formapago = pago, valor = monto, codauto = cod, digtar = dig, cantcouta = cuota },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+
+    public async Task<string> ActualizarProductoAsync(int leadId, string producto)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sam.ActualuzarLeadProducto",
+            new { leadid = leadId, productlead = producto },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+
+    public async Task<IEnumerable<Dictionary<string, object>>> MontosAsync(int ejecutivo)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var rows = await connection.QueryAsync(
+            "sige_sam_v3.BuscarLeadMontos",
+            new { ejecutivo },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        return rows.Select(r => (Dictionary<string, object>)(IDictionary<string, object>)r!);
+    }
+
+    public async Task<IEnumerable<Dictionary<string, object>>> ActividadesAsync(int leadId, string tipo)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var rows = await connection.QueryAsync(
+            "sige_sam_v3.BuscarActividadesLead",
+            new { id = leadId, tipoactividad = tipo },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        return rows.Select(r => (Dictionary<string, object>)(IDictionary<string, object>)r!);
+    }
+
+    public async Task<string> IngresarActividadAsync(int leadId, string tipo, string descripcion, string usuarioId)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sige_sam_v3.GrabaActividadesLead",
+            new { leadid = leadId, tipo, descripcion, usuarioid = usuarioId },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+
+    public async Task<string> EstadoUpdateAsync(int leadId, int estadoId)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sige_sam_v3.ActualizarEstadoLead",
+            new { leadid = leadId, estadolead = estadoId },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+
+    public async Task<IEnumerable<Dictionary<string, object>>> MotivosPerdidoAsync()
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var rows = await connection.QueryAsync(
+            "sige_sam_v3.BuscarMotivoLeadPerdido",
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        return rows.Select(r => (Dictionary<string, object>)(IDictionary<string, object>)r!);
+    }
+
+    public async Task<string> IngresarLeadPerdidoAsync(int leadId, int motivo, int estado)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sige_sam_v3.Lead_Ingresar_Perdido",
+            new { leadid = leadId, motivo, estado },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+
+    public async Task<string> ActualizarContactoAsync(int leadId, string nombre, string mail, string fono, string rut)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        await connection.ExecuteAsync(
+            "sige_sam_v3.ActualizaLeadContacto",
+            new { leadid = leadId, nombrecontacto = nombre, mailcontacto = mail, fonocontacto = fono, rutcontacto = rut },
+            commandType: System.Data.CommandType.StoredProcedure);
+        return "ok";
+    }
+}
diff --git a/backend/src/Ventas.Services/UsuarioService.cs b/backend/src/Ventas.Services/UsuarioService.cs
new file mode 100644
index 0000000..5c126b8
--- /dev/null
+++ b/backend/src/Ventas.Services/UsuarioService.cs
@@ -0,0 +1,55 @@
+using Dapper;
+using Npgsql;
+using Ventas.Core.DTOs;
+
+namespace Ventas.Services;
+
+public class UsuarioService
+{
+    private readonly string _connectionString;
+
+    public UsuarioService(string connectionString)
+    {
+        _connectionString = connectionString;
+    }
+
+    public async Task<LoginResponse?> LoginAsync(LoginRequest request)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var data = await connection.QueryAsync(
+            "sam.BuscarUsuario",
+            new { userid = request.Rut, passid = request.Clave },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        var user = data.FirstOrDefault();
+        if (user == null)
+            return null;
+
+        var dict = (IDictionary<string, object>)user;
+        return new LoginResponse
+        {
+            Nombre = dict["Nombres"]?.ToString() ?? "",
+            Sede = dict["idSede"]?.ToString()
+        };
+    }
+
+    public async Task<LoginResponse?> PerfilAsync(string usuarioId)
+    {
+        using var connection = new NpgsqlConnection(_connectionString);
+        var data = await connection.QueryAsync(
+            "sige_sam_v3.BuscarPerfilUsuario",
+            new { usuario = usuarioId },
+            commandType: System.Data.CommandType.StoredProcedure);
+
+        var user = data.FirstOrDefault();
+        if (user == null) return null;
+
+        var dict = (IDictionary<string, object>)user;
+        return new LoginResponse
+        {
+            Nombre = dict["Nombres"]?.ToString() ?? "",
+            Sede = dict["idSede"]?.ToString(),
+            Perfil = dict["Perfil"]?.ToString()
+        };
+    }
+}