diff --git a/app/admin/users/create/page.tsx b/app/admin/users/create/page.tsx
index a099bea..f8773fb 100644
--- a/app/admin/users/create/page.tsx
+++ b/app/admin/users/create/page.tsx
@@ -12,12 +12,14 @@ import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@
 import { Alert, AlertDescription } from "@/components/ui/alert"
 import { UserPlus, Copy, CheckCircle } from "lucide-react"
 import { createUserManually } from "../user-management-actions"
+import { useToast } from "@/hooks/use-toast"
 
 export default function CreateUserPage() {
   const router = useRouter()
   const [loading, setLoading] = useState(false)
   const [error, setError] = useState("")
   const [success, setSuccess] = useState<{ email: string; password: string } | null>(null)
+  const { toast } = useToast()
 
   const [formData, setFormData] = useState({
     email: "",
@@ -32,14 +34,35 @@ export default function CreateUserPage() {
     setLoading(true)
     setError("")
 
+    if (!formData.role) {
+      const message = "Please select a role for this user."
+      setError(message)
+      setLoading(false)
+      toast({
+        title: "Role required",
+        description: message,
+        variant: "destructive",
+      })
+      return
+    }
+
     const result = await createUserManually(formData)
 
     if (result.error) {
       setError(result.error)
       setLoading(false)
+      toast({
+        title: "Failed to create user",
+        description: result.error,
+        variant: "destructive",
+      })
     } else if (result.success && result.tempPassword) {
       setSuccess({ email: result.email, password: result.tempPassword })
       setLoading(false)
+      toast({
+        title: "User created",
+        description: "Temporary credentials have been generated.",
+      })
     }
   }
 
diff --git a/app/admin/users/existing-users-table.tsx b/app/admin/users/existing-users-table.tsx
index 7cec0f4..3a37f57 100644
--- a/app/admin/users/existing-users-table.tsx
+++ b/app/admin/users/existing-users-table.tsx
@@ -15,6 +15,8 @@ import {
 } from "@/components/ui/dialog"
 import { Label } from "@/components/ui/label"
 import { Textarea } from "@/components/ui/textarea"
+import { Alert, AlertDescription } from "@/components/ui/alert"
+import { useToast } from "@/hooks/use-toast"
 import { Edit, Ban, CheckCircle, Trash2 } from "lucide-react"
 import { updateUserRole, disableUser, enableUser, deleteUser } from "./user-management-actions"
 
@@ -39,40 +41,155 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
   const [deleteDialog, setDeleteDialog] = useState<{ open: boolean; userId?: string; userName?: string }>({
     open: false,
   })
-  const [loading, setLoading] = useState(false)
+  const [loadingUserId, setLoadingUserId] = useState<string | null>(null)
+  const [message, setMessage] = useState<{ type: "success" | "error"; text: string } | null>(null)
+  const { toast } = useToast()
 
   const handleUpdateRole = async () => {
     if (!roleDialog.userId) return
 
-    setLoading(true)
-    await updateUserRole(roleDialog.userId, selectedRole)
-    setLoading(false)
+     // Prevent demoting the last active admin
+    const targetUser = users.find((u) => u.id === roleDialog.userId)
+    const activeAdminCount = users.filter((u) => u.role === "admin" && u.is_active).length
+    const isDemotingLastAdmin =
+      targetUser && targetUser.role === "admin" && targetUser.is_active && selectedRole !== "admin" && activeAdminCount === 1
+
+    if (isDemotingLastAdmin) {
+      const message = "You cannot remove the last active admin. Create another admin first."
+      setMessage({ type: "error", text: message })
+      toast({
+        title: "Cannot change role",
+        description: message,
+        variant: "destructive",
+      })
+      return
+    }
+
+    setLoadingUserId(roleDialog.userId)
+    setMessage(null)
+    const result = await updateUserRole(roleDialog.userId, selectedRole)
+    setLoadingUserId(null)
     setRoleDialog({ open: false })
+    if (result?.error) {
+      setMessage({ type: "error", text: result.error })
+      toast({
+        title: "Failed to update role",
+        description: result.error,
+        variant: "destructive",
+      })
+    } else {
+      const msg = "User role updated successfully."
+      setMessage({ type: "success", text: msg })
+      toast({
+        title: "Role updated",
+        description: msg,
+      })
+    }
   }
 
   const handleDisable = async () => {
     if (!disableDialog.userId) return
 
-    setLoading(true)
-    await disableUser(disableDialog.userId, disableReason)
-    setLoading(false)
+    const targetUser = users.find((u) => u.id === disableDialog.userId)
+    const activeAdminCount = users.filter((u) => u.role === "admin" && u.is_active).length
+    const isDisablingLastAdmin =
+      targetUser && targetUser.role === "admin" && targetUser.is_active && activeAdminCount === 1
+
+    if (isDisablingLastAdmin) {
+      const message = "You cannot disable the last active admin. Create another admin first."
+      setMessage({ type: "error", text: message })
+      toast({
+        title: "Cannot disable user",
+        description: message,
+        variant: "destructive",
+      })
+      return
+    }
+
+    setLoadingUserId(disableDialog.userId)
+    setMessage(null)
+    const result = await disableUser(disableDialog.userId, disableReason)
+    setLoadingUserId(null)
     setDisableDialog({ open: false })
     setDisableReason("")
+    if (result?.error) {
+      setMessage({ type: "error", text: result.error })
+      toast({
+        title: "Failed to disable user",
+        description: result.error,
+        variant: "destructive",
+      })
+    } else {
+      const msg = "User disabled successfully."
+      setMessage({ type: "success", text: msg })
+      toast({
+        title: "User disabled",
+        description: msg,
+      })
+    }
   }
 
   const handleEnable = async (userId: string) => {
-    setLoading(true)
-    await enableUser(userId)
-    setLoading(false)
+    setLoadingUserId(userId)
+    setMessage(null)
+    const result = await enableUser(userId)
+    setLoadingUserId(null)
+    if (result?.error) {
+      setMessage({ type: "error", text: result.error })
+      toast({
+        title: "Failed to enable user",
+        description: result.error,
+        variant: "destructive",
+      })
+    } else {
+      const msg = "User enabled successfully."
+      setMessage({ type: "success", text: msg })
+      toast({
+        title: "User enabled",
+        description: msg,
+      })
+    }
   }
 
   const handleDelete = async () => {
     if (!deleteDialog.userId) return
 
-    setLoading(true)
-    await deleteUser(deleteDialog.userId)
-    setLoading(false)
+    const targetUser = users.find((u) => u.id === deleteDialog.userId)
+    const activeAdminCount = users.filter((u) => u.role === "admin" && u.is_active).length
+    const isDeletingLastAdmin =
+      targetUser && targetUser.role === "admin" && targetUser.is_active && activeAdminCount === 1
+
+    if (isDeletingLastAdmin) {
+      const message = "You cannot delete the last active admin. Create another admin first."
+      setMessage({ type: "error", text: message })
+      toast({
+        title: "Cannot delete user",
+        description: message,
+        variant: "destructive",
+      })
+      return
+    }
+
+    setLoadingUserId(deleteDialog.userId)
+    setMessage(null)
+    const result = await deleteUser(deleteDialog.userId)
+    setLoadingUserId(null)
     setDeleteDialog({ open: false })
+    if (result?.error) {
+      setMessage({ type: "error", text: result.error })
+      toast({
+        title: "Failed to delete user",
+        description: result.error,
+        variant: "destructive",
+      })
+    } else {
+      const msg = "User deleted successfully."
+      setMessage({ type: "success", text: msg })
+      toast({
+        title: "User deleted",
+        description: msg,
+      })
+    }
   }
 
   const roleColors: Record<string, string> = {
@@ -86,6 +203,13 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
 
   return (
     <>
+      {message && (
+        <div className="mb-4">
+          <Alert variant={message.type === "error" ? "destructive" : "default"}>
+            <AlertDescription>{message.text}</AlertDescription>
+          </Alert>
+        </div>
+      )}
       <Table>
         <TableHeader>
           <TableRow>
@@ -137,12 +261,18 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
                       size="sm"
                       variant="outline"
                       onClick={() => setDisableDialog({ open: true, userId: user.id })}
+                      disabled={loadingUserId === user.id}
                     >
                       <Ban className="mr-1 h-4 w-4" />
                       Disable
                     </Button>
                   ) : (
-                    <Button size="sm" variant="outline" onClick={() => handleEnable(user.id)} disabled={loading}>
+                    <Button
+                      size="sm"
+                      variant="outline"
+                      onClick={() => handleEnable(user.id)}
+                      disabled={loadingUserId === user.id}
+                    >
                       <CheckCircle className="mr-1 h-4 w-4" />
                       Enable
                     </Button>
@@ -157,7 +287,7 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
                         userName: `${user.first_name || ""} ${user.last_name || ""}`.trim() || user.email,
                       })
                     }
-                  >
+                    >
                     <Trash2 className="mr-1 h-4 w-4" />
                     Delete
                   </Button>
@@ -195,7 +325,10 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
             <Button variant="outline" onClick={() => setRoleDialog({ open: false })}>
               Cancel
             </Button>
-            <Button onClick={handleUpdateRole} disabled={loading}>
+            <Button
+              onClick={handleUpdateRole}
+              disabled={roleDialog.userId ? loadingUserId === roleDialog.userId : false || !selectedRole}
+            >
               Update Role
             </Button>
           </DialogFooter>
@@ -223,7 +356,11 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
             <Button variant="outline" onClick={() => setDisableDialog({ open: false })}>
               Cancel
             </Button>
-            <Button variant="destructive" onClick={handleDisable} disabled={!disableReason || loading}>
+            <Button
+              variant="destructive"
+              onClick={handleDisable}
+              disabled={!disableReason || (disableDialog.userId ? loadingUserId === disableDialog.userId : false)}
+            >
               Disable User
             </Button>
           </DialogFooter>
@@ -243,7 +380,11 @@ export function ExistingUsersTable({ users }: { users: User[] }) {
             <Button variant="outline" onClick={() => setDeleteDialog({ open: false })}>
               Cancel
             </Button>
-            <Button variant="destructive" onClick={handleDelete} disabled={loading}>
+            <Button
+              variant="destructive"
+              onClick={handleDelete}
+              disabled={deleteDialog.userId ? loadingUserId === deleteDialog.userId : false}
+            >
               Delete Permanently
             </Button>
           </DialogFooter>
diff --git a/app/admin/users/pending-registrations-table.tsx b/app/admin/users/pending-registrations-table.tsx
index 82fb87b..ce68e38 100644
--- a/app/admin/users/pending-registrations-table.tsx
+++ b/app/admin/users/pending-registrations-table.tsx
@@ -18,6 +18,7 @@ import { Textarea } from "@/components/ui/textarea"
 import { CheckCircle, XCircle, Copy } from "lucide-react"
 import { approveRegistration, rejectRegistration } from "./user-management-actions"
 import { Alert, AlertDescription } from "@/components/ui/alert"
+import { useToast } from "@/hooks/use-toast"
 
 interface Registration {
   id: string
@@ -37,17 +38,42 @@ export function PendingRegistrationsTable({ registrations }: { registrations: Re
   const [rejectDialog, setRejectDialog] = useState<{ open: boolean; registrationId?: string }>({ open: false })
   const [rejectionReason, setRejectionReason] = useState("")
   const [loading, setLoading] = useState<string | null>(null)
+  const [error, setError] = useState<string | null>(null)
+  const { toast } = useToast()
 
   const handleApprove = async (registrationId: string) => {
+    setError(null)
     const assignedRole =
       selectedRoles[registrationId] || registrations.find((r) => r.id === registrationId)?.requested_role
 
+    if (!assignedRole) {
+      const message = "Please select a role before approving this registration."
+      setError(message)
+      toast({
+        title: "Role required",
+        description: message,
+        variant: "destructive",
+      })
+      return
+    }
+
     setLoading(registrationId)
-    const result = await approveRegistration(registrationId, assignedRole!)
+    const result = await approveRegistration(registrationId, assignedRole)
     setLoading(null)
 
     if (result.success && result.tempPassword) {
       setApprovalDialog({ open: true, email: result.email, password: result.tempPassword })
+      toast({
+        title: "User approved",
+        description: "The user account has been created successfully.",
+      })
+    } else if (result.error) {
+      setError(result.error)
+      toast({
+        title: "Failed to approve user",
+        description: result.error,
+        variant: "destructive",
+      })
     }
   }
 
@@ -55,10 +81,23 @@ export function PendingRegistrationsTable({ registrations }: { registrations: Re
     if (!rejectDialog.registrationId) return
 
     setLoading(rejectDialog.registrationId)
-    await rejectRegistration(rejectDialog.registrationId, rejectionReason)
+    const result = await rejectRegistration(rejectDialog.registrationId, rejectionReason)
     setLoading(null)
     setRejectDialog({ open: false })
     setRejectionReason("")
+
+    if (result?.error) {
+      toast({
+        title: "Failed to reject registration",
+        description: result.error,
+        variant: "destructive",
+      })
+    } else {
+      toast({
+        title: "Registration rejected",
+        description: "The registration request has been rejected.",
+      })
+    }
   }
 
   const copyCredentials = () => {
@@ -77,6 +116,13 @@ export function PendingRegistrationsTable({ registrations }: { registrations: Re
 
   return (
     <>
+      {error && (
+        <div className="mb-4">
+          <Alert variant="destructive">
+            <AlertDescription>{error}</AlertDescription>
+          </Alert>
+        </div>
+      )}
       <Table>
         <TableHeader>
           <TableRow>
diff --git a/app/admin/users/pending-team-members-table.tsx b/app/admin/users/pending-team-members-table.tsx
index cbf8e27..db99ce7 100644
--- a/app/admin/users/pending-team-members-table.tsx
+++ b/app/admin/users/pending-team-members-table.tsx
@@ -16,6 +16,7 @@ import {
 import { CheckCircle, Copy } from "lucide-react"
 import { approveTeamMember } from "./user-management-actions"
 import { Alert, AlertDescription } from "@/components/ui/alert"
+import { useToast } from "@/hooks/use-toast"
 
 interface TeamMember {
   id: string
@@ -33,18 +34,41 @@ export function PendingTeamMembersTable({ teamMembers }: { teamMembers: TeamMemb
     open: false,
   })
   const [loading, setLoading] = useState<string | null>(null)
+  const [error, setError] = useState<string | null>(null)
+  const { toast } = useToast()
 
   const handleApprove = async (teamMemberId: string) => {
+    setError(null)
     const assignedRole = selectedRoles[teamMemberId] || teamMembers.find((tm) => tm.id === teamMemberId)?.role
 
+    if (!assignedRole) {
+      const message = "Please select a role before approving this team member."
+      setError(message)
+      toast({
+        title: "Role required",
+        description: message,
+        variant: "destructive",
+      })
+      return
+    }
+
     setLoading(teamMemberId)
-    const result = await approveTeamMember(teamMemberId, assignedRole!)
+    const result = await approveTeamMember(teamMemberId, assignedRole)
     setLoading(null)
 
     if (result.success && result.tempPassword) {
       setApprovalDialog({ open: true, email: result.email, password: result.tempPassword })
+      toast({
+        title: "Team member approved",
+        description: "The user account has been created successfully.",
+      })
     } else if (result.error) {
-      alert(result.error)
+      setError(result.error)
+      toast({
+        title: "Failed to approve team member",
+        description: result.error,
+        variant: "destructive",
+      })
     }
   }
 
@@ -64,6 +88,13 @@ export function PendingTeamMembersTable({ teamMembers }: { teamMembers: TeamMemb
 
   return (
     <>
+      {error && (
+        <div className="mb-4">
+          <Alert variant="destructive">
+            <AlertDescription>{error}</AlertDescription>
+          </Alert>
+        </div>
+      )}
       <Table>
         <TableHeader>
           <TableRow>