Cross Selling in Multi-Disciplinary Firms

Cross-selling is the practice of introducing complementary services to existing clients, a strategy especially powerful for multi-disciplinary firms. Rather than chasing new business, professionals deepen relationships by solving more of a client’s challenges through integrated offerings. This approach lowers acquisition costs, increases win rates, and cements firms as trusted advisors. With examples from engineering, architecture, and environmental consulting, cross-selling demonstrates how one service engagement can open doors to broader collaborations.

This series explores cross-selling in multi-disciplinary firms, where opportunities often go unrealized because teams stay siloed. Effective cross-selling isn’t about being pushy with clients—it’s about creating regular, proactive conversations between colleagues. Twennie’s prompt set introduces five small but powerful activities—knowledge swaps, coffee talks, project sheet exchanges, problem-solving sessions, and friendly competitions—that make cross-disciplinary collaboration routine rather than rare.

Cross-selling is often talked about but rarely practiced well in multi-disciplinary firms. This prompt set provides 20 concrete activities your teams can try right away—short, time-boxed experiments like joint coffee chats, exchanging project sheets, shadowing client calls, or creating “combo case” slides. Each exercise encourages collaboration, sparks curiosity about other disciplines, and surfaces hidden opportunities to expand work with existing clients.

Cross-selling sounds simple—connect clients with more of your firm’s services—but in practice, it rarely happens consistently. Why? Professionals often avoid talking across departments, relying on sporadic meetings that miss opportunities. This series tackles the excuses and re-frames cross-selling as proactive communication between colleagues. Through short, practical activities like coffee talks, project sheet swaps, and problem-solving sessions, you’ll learn to build pathways that uncover opportunities, strengthen relationships, and present clients with integrated solutions.