This document provides an overview of multidimensional scaling (MDS) and overall similarity perceptual maps. It discusses the challenges with attribute rating perceptual maps and how MDS can help address these challenges by mapping similarities and dissimilarities among items based on consumer perceptions. The document outlines the history, methodology, implementation steps, and example application of MDS for creating a perceptual map of search engines. Key considerations for using MDS include having a large sample size of subjects and brands/products.