How can I implement the generic repository pattern and improve the performance for the code below?

public class OfficeDTO
{
    public IEnumerable<employeedto> Employees { get; set; }
    public IEnumerable<departmentdto> Departments { get; set; }
}

public class EmployeeDTO
{
   public int EmpId { get; set; }
   public string EmpName { get; set; }
}

public class DepartmentDTO
{
    public string DeptCode { get; set; }
    public string DeptName { get; set; }
}

public ActionResult Index()
          {
              EF.OfficeEntities ctx = new EF.OfficeEntities();
              Models.OfficeDTO office = new Models.OfficeDTO();

              using (ctx)
              {

                  var empList = ctx.GetEmployeesByYearJoined("2009")
                            .ToList();

                  var empResults = (from q in empList
                                 select new Models.EmployeeDTO
                                 {
                                     EmpId = q.EmpID,
                                     EmpName = q.FirstName + q.LastName
                                 }).ToList();
                  office.Employees = empResults;

                  var depResults = (from q in ctx.Departments
                                    select new Models.DepartmentDTO
                                    {
                                        DeptCode = q.DepartmentCode,
                                        DeptName = q.DepartmentName

                                    }).ToList();
                  office.Departments = depResults;
              }

              return View(office);
          }</departmentdto></employeedto>