This paper focuses on patterns of technological change and on the impact of technological breakthroughs on environmental conditions. Using data from the minicomputer, cement, and airline industries from their births through 1980, we demonstrate that technology evolves through periods of incremental change punctuated by technological break-throughs that either enhance or destroy the competence of firms in an industry. These breakthroughs, or technological discontinuities, significantly increase both environmental uncertainty and munificence. The study shows that while competence-destroying discontinuities are initiated by new firms and are associated with increased environmental turbulence, competence-enhancing discontinuities are initiated by existing firms and are associated with decreased environmental turbulence. These effects decrease over successive discontinuities. Those firms that initiate major technological changes grow more rapidly than other firms.