I develop a theoretical framework for studying choice bracketing based on general preference axioms. A decision maker is characterized by a system of brackets with coarser systems of brackets corresponding to a less narrow view of the decision environment. For each bracket the decision maker evaluates the dimensions of her choice inside the bracket jointly, while keeping all dimensions outside the bracket fixed at the reference level. As a consequence, the narrow decision maker underestimates the complementarities and substitutabilities between dimensions that are in distinct brackets and behaves as if she would apply a budgeting heuristic.