Strangeness in compact stars and signal of deconfinement

Phase transitions in compact stars are discussed including hyperonization, deconfinement and crystalline phases. Reasons why kaon condensation is unlikely are reviewed. Particular emphasis is placed on the evolution of internal structure with spin-down of pulsars. A signature of a first-order phase transition in the timing structure of pulsars, which is strong and easy to measure, is identified. (author)