While polymer brush systems continue to grow in popularity, so does their complexity and sophistication. Advances in polymerization and specific functionalization methods have led to novel applications in diverse research fields. The marriage of top-down lithography with bottom-up brush processing is becoming increasingly important in the development and progress of nanotechnology. The aim of this review is to examine different approaches taken to generate tailored polymer brush systems through surface-initiated polymerizations as well as patterning techniques. Detaching polymer brushes to create free-standing membranes is also highlighted and discussed in terms of methods and characterization. (c) 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1457-1472