New information technology developments continue to have a significant impact on large-scale architectural/engineering/construction (A/E/C) projects. However, the issue of whether A/E/C organizations are receiving adequate returns from their information technology (IT) investments remains an important managerial concern. Earlier work on financial models has concentrated on firm-wide strategies for maximizing the return of investments. Traditional financial models for measuring the value of information technology investments typically work well for static business strategies and single business scenarios. These models are inappropriate for large-scale A/E/C projects, which typically have multiple firms participating over a fixed project life cycle and proportionately splitting the cumulative benefits accrued over the project life cycle after their involvement on the project. To resolve these issues, the paper proposes a strategic planning framework based on IT diffusion for maximizing the value of investments in strategic capabilities. The essential steps in the strategic planning framework include environmental scan, internal scrutiny, IT diffusion analysis, and IT investment modeling. To demonstrate the framework and an integrated approach to IT investment planning, the paper presents a case study based on a large-scale A/E/C project.