BLOSOM: a framework for mining arbitrary boolean expressions. We introduce a novel framework, called BLOSOM, for mining (frequent) boolean expressions over binary-valued datasets. We organize the space of boolean expressions into four categories: pure conjunctions, pure disjunctions, conjunction of disjunctions, and disjunction of conjunctions. We focus on mining the simplest expressions the minimal generators for each class. We also propose a closure operator for each class that yields closed boolean expressions. BLOSOM efficiently mines frequent boolean expressions by utilizing a number of methodical pruning techniques. Experiments showcase the behavior of BLOSOM, and an application study on a real dataset is also given.