Current assumptions and conclusions in several active areas of amyloid research are examined to see how consistent the data from chosen in vitro and in vivo model systems are with clinical and anatomic observations. These areas include the assembly of amyloid-like fibrils in vitro, the nucleation phenomenon, amyloid fibril structure in vivo and in vitro, common structural components of the amyloids, and the regression of tissue amyloid and proteolysis of amyloid proteins. Divergences and congruencies are highlighted, which in turn suggests caution in the interpretation of present data, greater collaboration and communication among investigators, and, additional areas and techniques for investigation.