Revenue is the lifeblood of the combined company—and the most vulnerable asset during integration. Customers get nervous about acquisitions. Competitors exploit the transition. Sales teams get distracted by internal politics. Protecting the revenue base while unlocking cross-sell is the customer integration challenge.

Customer communication should happen immediately after close—often the same day. The message: nothing changes (for now), you're in good hands, here's who to call. Silence invites competitors to spread FUD (fear, uncertainty, doubt) and steal accounts.

Sales integration is equally sensitive. Territory redesign, quota resets, account reassignment—these decisions affect commissions and careers. Handle them poorly and your best salespeople leave. Handle them well and you have a unified team ready to cross-sell.