In 1967, IBM approached Breuer’s office about designing a 60,000 square foot expansion to the Research Center they had completed just five years earlier. Breuer and Gatje are credited as architects for the expansion with Mario Jossa as partner-in-charge. All parties wanted to preserve the profile of the original building and so Breuer created two new wings abutting the hillside. Breuer further disguised the expansion by locating the first volume underneath the existing terrace and adjacent to the ramp leading to the terrace. The offices in the expansion were slightly smaller than those in the original building and were meant to accommodate a single engineer. The second expansion was overseen by MBA, the successor firm to Marcel Breuer and Associates, after Breuer's retirement.