This paper offers a brief review of the history and development of macroporous ion-exchange and adsorbent resins, starting with the condensate polymers in the early forties, continuing with the addition polymers of the late fifties, and evolving into new adsorbents for a variety of interesting applications. The review also alludes to the effects of various methods of preparation on the physical properties and internal structure of the (macroporous) resins produced. The emphasis is on the commercial aspects of ion-exchange development.