Each Fat Cat volume contains the contents of three successive compilations stacked back to back. There are two types of Fat Cat books, one features black and white strips and one featuring full color strips. Volumes 1 to 12 have been released in black and white, but some have since been reissued in full color. The black and white strips were published semiannually up to Vol. 11 (compilations 31–33) in 1999. Since then, the publication schedule has slowed: Vol. 12 (compilations 34–36) was published in 2001, followed by Vol. 13 (compilations 37–39) in 2006.