The early phases of a product development project (Le., concept generation and product planning) are commonly acknowledged to play a central role in the success of product innovation. Early decisions are unlikely to be changed during downstream phases, unless high costs and time are experienced. They have therefore the highest influence on project performance. However, early analysis and problem solving is also a difficult task, because the necessary information and insights are not available until one gets into detailed design. Most companies are locked in this dilemma between anticipation (i.e., anticipating decisions in the early phases of product development, where influence on performance is substantial) and reaction (i.e., delaying decisions to downstream phases, where information and opportunities are manifest). This article investigates early development practices in 18 Italian and Swedish companies, operating in the vehicle, helicopter, and white-goods industries. It shows that neither anticipation nor reaction may be considered a best practice in absolute terms. Rather, it identifies four possible approaches to manage the early phases (detailed, selective, comprehensive, and postponed), where anticipation and reaction have different balances. In addition, the article shows how anticipation and reaction are not contradictory or mutually exclusive, but strongly interact with each other through a mechanism that we call planned flexibility, i.e., the capability to build flexibility into the development process due to decisions taken early in the project. (C) 1999 Elsevier Science Inc.