There is a close-knit complex of philosophical problems which has been with us since antiquity. These problems involve such concepts as potentiality and disposition; necessity, actuality, and possibility; and even material and subjunctive implication. They are philosophically ubiquitous, cropping up in a range of fields broad enough to include metaphysics, epistemology, philosophy of science, logic, philosophy of language, and ethics. They seem, moreover, to be strangely recalcitrant. It is to this set of perennial philosophical problems that Hans Reichenbach's 1954 monograph — originally published under the title Nomological Statements and Admissible Operations, but reissued in 1976 under the title Laws, Modalities, and Counterfactuals — is addressed. The new title has been adopted to provide the philosophical community with a clearer idea of the subject matter of the book (the original pagination is retained).