diff --git a/internal/slurm/slurmdb_users.go b/internal/slurm/slurmdb_users.go
new file mode 100644
index 0000000..a0b6147
--- /dev/null
+++ b/internal/slurm/slurmdb_users.go
@@ -0,0 +1,155 @@
+package slurm
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+)
+
+// GetUsersOptions specifies optional parameters for GetUsers and GetUser.
+type GetUsersOptions struct {
+	AdminLevel      *string `url:"admin_level,omitempty"`
+	DefaultAccount  *string `url:"default_account,omitempty"`
+	DefaultWckey    *string `url:"default_wckey,omitempty"`
+	WithAssocs      *string `url:"with_assocs,omitempty"`
+	WithCoords      *string `url:"with_coords,omitempty"`
+	WithDeleted     *string `url:"with_deleted,omitempty"`
+	WithWckeys      *string `url:"with_wckeys,omitempty"`
+	WithoutDefaults *string `url:"without_defaults,omitempty"`
+}
+
+// GetUsers lists all users.
+func (s *SlurmdbUsersService) GetUsers(ctx context.Context, opts *GetUsersOptions) (*OpenapiUsersResp, *Response, error) {
+	path := "slurmdb/v0.0.40/users"
+	req, err := s.client.NewRequest("GET", path, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	if opts != nil {
+		u, parseErr := url.Parse(req.URL.String())
+		if parseErr != nil {
+			return nil, nil, parseErr
+		}
+		q := u.Query()
+		if opts.AdminLevel != nil {
+			q.Set("admin_level", *opts.AdminLevel)
+		}
+		if opts.DefaultAccount != nil {
+			q.Set("default_account", *opts.DefaultAccount)
+		}
+		if opts.DefaultWckey != nil {
+			q.Set("default_wckey", *opts.DefaultWckey)
+		}
+		if opts.WithAssocs != nil {
+			q.Set("with_assocs", *opts.WithAssocs)
+		}
+		if opts.WithCoords != nil {
+			q.Set("with_coords", *opts.WithCoords)
+		}
+		if opts.WithDeleted != nil {
+			q.Set("with_deleted", *opts.WithDeleted)
+		}
+		if opts.WithWckeys != nil {
+			q.Set("with_wckeys", *opts.WithWckeys)
+		}
+		if opts.WithoutDefaults != nil {
+			q.Set("without_defaults", *opts.WithoutDefaults)
+		}
+		u.RawQuery = q.Encode()
+		req.URL = u
+	}
+
+	var result OpenapiUsersResp
+	resp, err := s.client.Do(ctx, req, &result)
+	if err != nil {
+		return nil, resp, err
+	}
+	return &result, resp, nil
+}
+
+// GetUser gets a single user by name.
+func (s *SlurmdbUsersService) GetUser(ctx context.Context, userName string, opts *GetUsersOptions) (*OpenapiUsersResp, *Response, error) {
+	path := fmt.Sprintf("slurmdb/v0.0.40/user/%s", userName)
+	req, err := s.client.NewRequest("GET", path, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	if opts != nil {
+		u, parseErr := url.Parse(req.URL.String())
+		if parseErr != nil {
+			return nil, nil, parseErr
+		}
+		q := u.Query()
+		if opts.WithDeleted != nil {
+			q.Set("with_deleted", *opts.WithDeleted)
+		}
+		if opts.WithAssocs != nil {
+			q.Set("with_assocs", *opts.WithAssocs)
+		}
+		if opts.WithCoords != nil {
+			q.Set("with_coords", *opts.WithCoords)
+		}
+		if opts.WithWckeys != nil {
+			q.Set("with_wckeys", *opts.WithWckeys)
+		}
+		u.RawQuery = q.Encode()
+		req.URL = u
+	}
+
+	var result OpenapiUsersResp
+	resp, err := s.client.Do(ctx, req, &result)
+	if err != nil {
+		return nil, resp, err
+	}
+	return &result, resp, nil
+}
+
+// PostUsers updates users.
+func (s *SlurmdbUsersService) PostUsers(ctx context.Context, body *OpenapiUsersResp) (*OpenapiUsersResp, *Response, error) {
+	path := "slurmdb/v0.0.40/users"
+	req, err := s.client.NewRequest("POST", path, body)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var result OpenapiUsersResp
+	resp, err := s.client.Do(ctx, req, &result)
+	if err != nil {
+		return nil, resp, err
+	}
+	return &result, resp, nil
+}
+
+// PostUsersAssociation adds users with conditional association.
+func (s *SlurmdbUsersService) PostUsersAssociation(ctx context.Context, body *OpenapiUsersAddCondResp) (*OpenapiUsersAddCondRespStr, *Response, error) {
+	path := "slurmdb/v0.0.40/users_association"
+	req, err := s.client.NewRequest("POST", path, body)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var result OpenapiUsersAddCondRespStr
+	resp, err := s.client.Do(ctx, req, &result)
+	if err != nil {
+		return nil, resp, err
+	}
+	return &result, resp, nil
+}
+
+// DeleteUser deletes a user by name.
+func (s *SlurmdbUsersService) DeleteUser(ctx context.Context, userName string) (*OpenapiResp, *Response, error) {
+	path := fmt.Sprintf("slurmdb/v0.0.40/user/%s", userName)
+	req, err := s.client.NewRequest("DELETE", path, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var result OpenapiResp
+	resp, err := s.client.Do(ctx, req, &result)
+	if err != nil {
+		return nil, resp, err
+	}
+	return &result, resp, nil
+}
diff --git a/internal/slurm/slurmdb_users_test.go b/internal/slurm/slurmdb_users_test.go
new file mode 100644
index 0000000..1d2e342
--- /dev/null
+++ b/internal/slurm/slurmdb_users_test.go
@@ -0,0 +1,160 @@
+package slurm
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestSlurmdbUsersService_GetUsers(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/users", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+		fmt.Fprint(w, `{"users": [{"name": "testuser"}]}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	resp, _, err := client.SlurmdbUsers.GetUsers(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp == nil {
+		t.Fatal("expected non-nil response")
+	}
+}
+
+func TestSlurmdbUsersService_GetUsersWithOptions(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/users", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+		if r.URL.Query().Get("with_deleted") != "true" {
+			t.Error("expected with_deleted=true query param")
+		}
+		if r.URL.Query().Get("with_assocs") != "true" {
+			t.Error("expected with_assocs=true query param")
+		}
+		fmt.Fprint(w, `{"users": [{"name": "testuser"}]}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	deleted := "true"
+	assocs := "true"
+	opts := &GetUsersOptions{WithDeleted: &deleted, WithAssocs: &assocs}
+	resp, _, err := client.SlurmdbUsers.GetUsers(context.Background(), opts)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp == nil {
+		t.Fatal("expected non-nil response")
+	}
+}
+
+func TestSlurmdbUsersService_GetUser(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/user/testuser", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+		fmt.Fprint(w, `{"users": [{"name": "testuser"}]}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	resp, _, err := client.SlurmdbUsers.GetUser(context.Background(), "testuser", nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp == nil {
+		t.Fatal("expected non-nil response")
+	}
+}
+
+func TestSlurmdbUsersService_PostUsers(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/users", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "POST")
+		fmt.Fprint(w, `{"users": [{"name": "testuser"}]}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	body := &OpenapiUsersResp{}
+	resp, _, err := client.SlurmdbUsers.PostUsers(context.Background(), body)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp == nil {
+		t.Fatal("expected non-nil response")
+	}
+}
+
+func TestSlurmdbUsersService_PostUsersAssociation(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/users_association", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "POST")
+		fmt.Fprint(w, `{"added_users": "user1,user2"}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	body := &OpenapiUsersAddCondResp{}
+	resp, _, err := client.SlurmdbUsers.PostUsersAssociation(context.Background(), body)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp == nil {
+		t.Fatal("expected non-nil response")
+	}
+	if resp.AddedUsers == nil {
+		t.Fatal("expected non-nil AddedUsers")
+	}
+	if *resp.AddedUsers != "user1,user2" {
+		t.Errorf("expected added_users 'user1,user2', got %s", *resp.AddedUsers)
+	}
+}
+
+func TestSlurmdbUsersService_DeleteUser(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/user/testuser", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "DELETE")
+		fmt.Fprint(w, `{"meta": {"plugin": {"type": "openapi/v0.0.40"}}}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	resp, _, err := client.SlurmdbUsers.DeleteUser(context.Background(), "testuser")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if resp == nil {
+		t.Fatal("expected non-nil response")
+	}
+}
+
+func TestSlurmdbUsersService_GetUsers_Error(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/slurmdb/v0.0.40/users", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusInternalServerError)
+		fmt.Fprint(w, `{"errors": [{"error": "internal error"}]}`)
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	client, _ := NewClient(server.URL, nil)
+	_, _, err := client.SlurmdbUsers.GetUsers(context.Background(), nil)
+	if err == nil {
+		t.Fatal("expected error for 500 response")
+	}
+	if !strings.Contains(err.Error(), "500") {
+		t.Errorf("expected error to contain 500, got %v", err)
+	}
+}