(consisting of a pair of birds) cannot have both birds offered as one type of sacrifice. The result is that if birds become mixed up (whether completely or a number of birds flies from one group to another), certain birds are disqualified from being offered. It is the laws of these complications that form the subject of tractate Kinnim.

The tractate consists of three chapters:
*Chapter 1 deals largely with cases where birds flew into a designated group or where different groups of birds became totally mixed up.
*Chapter 2 considers