The goal of the current paper is to provide an introduction to and survey of the diverse landscape of relevant alternatives theories of knowledge. Emphasis is placed throughout both on the abstractness of the relevant alternatives approach and its amenability to formalization through logical techniques. We present some of the important motivations for adopting the relevant alternatives approach; briefly explore the connections and contrasts between the relevant alternatives approach and related developments in logic, epistemology and philosophy of science; provide a schema for classifying and studying relevant alternatives theories at different levels of abstraction; and present a sample of relevant alternatives theories (contrasting what we call question-first and topic-first theories) that tie our discussion to on-going debates in the philosophical literature, as well as showcasing techniques for formalizing some of the important positions in these debates