stopping the same form from loading 2 times ?

The easiest way I can think of is to have a single class field. If it's null, create a new instance and display it. If it isn't null, do nothing. Then attach a delegate to the event so that the field is disposed and null again once you close the form. For example class Form1{ yourForm formVariable; public void button1_Click (object sender, System.EventArgs e) { if (formVariable != null) { formVariable = new yourForm(...); formVariable.Closed += new System.EventArgs(formVariable_Closed); formVariable.Show(); } } public void formVariable_Closed(...) { formVariable.Dispose(); formVariable = null; } }