The paper addresses the issue of the potential impact of technological innovation on competition. It aims at reviewing Abernathy and Utterback's dominant technology, Dosi's technological trajectories, Clark's design hierarchies, Abernathy and Clark's transilience concepts. We recognize that the intensity of innovation falls along a continuum and introduce the concept of "micro-radical" innovation. We choose to qualify the strategic significance of technological change through the transilience concept, leading to the principle of "competence relatedness". We introduce Dual Technological Trees (DTT) as a way to present a hierarchical map of the many technological options that may be searched to fulfil a certain generic function in the market place. The complex and unpredictable nature of technology is recognized: the paper essentially suggests to map the various technological options and suboptions that one would think plausible al the present time, keeping in mind that technology will end up finding its own peculiar ways. The dynamic interaction between the DTT and some "Customer Concept Tree" on the market side is also discussed. We finally turn to the use of the DTT to assess the potential strategic significance of innovation. Several examples are presented.