This experience paper presents observations, lessons learned, and recommendations based on a case study of reuse. The case study is concerned with the development, maturation, and reuse of a business domain independent software component (horizontal reuse) in a project-driven organisation that has little previous experience with systematic software reuse. The main lessons learned are that: (a) even though domain analysis can alleviate reuse mismatch problems one should not underestimate the technical problems that may arise when reusing; (b) a side-effect of reuse is that software engineering knowledge is transferred within an organisation; (c) design patterns can be as risky as they can be beneficial; and (d) there is more to architectural mismatch than “merely” packaging mismatch.