Making subreports invesible

[Simon]

I have this repot that has 3 text boxes

Summer Brochure
Winter Brochure
Skiing Brochure


Which will have -1 or 0 depending if true or false


I also have 3 sub reports for each brochure


How can i set it to make the a subreport invesiable if one of the
brochures is false 0


Thanks