To reproduce: - Add a RadGridView and a button to a blank form. - Subscribe to CellValidating event from the grid and set the cancel property of the CellValidatingEventArgs to true upon some condition. - Add click event handler for the button and print a message in it. - Start the application and enter some invalid data in the grid cell, then click the button. - The code from the button's event handler is executed. Workaround use a flag to determine when to execute the corresponding button code: bool validating = false; void radGridView1_CellValidating(object sender, Telerik.WinControls.UI.CellValidatingEventArgs e) { if (e.Value.ToString().Length < 5) { e.Cancel = true; validating = true; e.Row.ErrorText = "Validation error!"; } else { validating = false; } } private void radButton1_Click(object sender, EventArgs e) { if (!validating) { Debug.WriteLine("Executed"); } }