Success in stock selection depends in large part on proper appraisal of the broad investment framework. Failure to avoid over-priced stocks may result (1) from the failure to recognize the change in the investment framework or (2) from slowness to adapt stock selection to the new framework. By way of illustration, this article summarizes changes in the broad framework from the 1920’s to the 1930’s and again into the postwar period. An attempt is made to identify the present framework and to suggest how recognition of this framework might be applied to the problem of stock selection.