Polymers are used in commercial and proposed electrochromic devices as everything from the electrochromic materials themselves to solution thickeners, the matrix or solid phase of gels, solid polymer electrolytes and sealants. Each type of application of polymers in electrochromics is discussed and several definitions are compared with regard to gels and solution-based electrochromic redox systems. A review of electrochromics and polymer gels, especially from the perspective of the extensive patent literature on the subject, is given.