>I have a grid in my form and the grid headers have code in the CLICK() event.
>
>I want the users to be able to click the headers whenever they want, but I also want them to be able to resize a grid column or even move a grid column.
>
>However, when they resize or move a column, the CLICK() event code is also called.
>
>How can I prevent the CLICK() code from firing when the user resizes or moves a grid column?

Cemal has it right, put a flag in the column Resize to check and re-set if necessary in the header click. I would only add that I put the same flag in the Moved event also, for same reason. Something like

in column Resize, Moved:

this.parent.lNosort = .T.

in Header.click:

if this.parent.parent.lNosort 
  this.parent.parent.lNosort = .F.
  return
endif

otherwise go ahead and do your sort.