Generative artificial intelligence is triggering a range of emotions in legal departments—from anxiety to exhilaration—but early adopters already have reached an epiphany: It’s going to make them more effective strategic business advisers, the yardstick of success for in-house attorneys these days.

Whether they’re the only lawyer at their company or part of a department of 1,000, in-house counsel are putting tools like ChatGPT, Claude and Bard to use for more than just drafting contracts and legal memos. They’re using them to comb through vast repositories of data, summarize long, complicated legal documents and find opportunities to advance business.