Book excerpt: Here, several leading experts in the area of cognitive science summarize their current research programs, tracing Herbert A. Simon's influence on their own work -- and on the field of information processing at large. Topics covered include problem- solving, imagery, reading, writing, memory, expertise, instruction, and learning. Collectively, the chapters reveal a high degree of coherence across the various specialized disciplines within cognition -- a coherence largely attributable to the initial unity in Simon's seminal and pioneering contributions.