>SET SAFETY OFF
>SET EXCLUSIVE on
>USE bookings IN 0 EXCLUSIVE &&I have tried it with and without the exclusive clause. Makes no difference.

At this point, since you included an "IN 0" clause, if there is any table opened in the current work area all the following commands and functions will refer to it, not to the "bookings" work area.

>DELETE ALL
>PACK
>IF ISEXCLUSIVE( ) &&Just to check if there is exclusivity. returns .f. each time - no matter what I change around in the code.
> MESSAGEBOX('Table opened exclusive')
>ELSE
>  MESSAGEBOX('Not opened exclusively')
>ENDIF
>SET EXCLUSIVE OFF
>SET SAFETY ON

So, before the previous bunch of code, a

SELECT bookings

is required to make sure you're targeting "bookings", and not something else.