Body allows the code for a method to be created outside the class definition (or to be replaced outside). package require Itcl itcl::class helloworld { public variable owner "No-one" method greet {} { puts "Hello World from $owner" } } helloworld h1 h1 configure -owner Me h1 greet # change the behaviour of helloworld itcl::body helloworld::greet {} { puts "Goodbye Cruel World from $owner" } h1 greet Will use the original greet (Hello world...) up to the itcl::body command. Then greet is replaced. Commonly used to prevent class definitions becoming too long to read - a long method should be placed outside the class definition as an itcl::body. [GWM]