What is the meaning of the idiom get your hands dirty?

To "get ones hands dirty" can mean:

1) to get involved in the details of something (such as a process, design, creation, or other often cooperative venture);

2) to get personally involved in some unsavory venture (often used when certain people, such as politicians, send others to "do the dirty work" of war, assassinations, etc., because they don't want to "get their hands dirty")