The New York based law firm of Birbrower, Montalbano, Condon & Frank, P.C. (Birbrower) (plaintiff) entered into a fee agreement with ESQ, a corporation based in California. The fee agreement related to a dispute between ESQ and another company headquartered in California. The fee agreement declared that it should be governed by the laws of California. Birbrower was not licensed to practice law in the state of California. Birbrower performed some work under the agreement from the firm’s New York office. However, the bulk of the work involved lawyers with Birbrower traveling to California for meetings, negotiations, and preparation for private arbitration proceedings. After the relationship between Birbrower and ESQ broke down, ESQ sued Birbrower for malpractice, alleging that Birbrower had engaged in the unauthorized practice of law. Birbrower counterclaimed to enforce its fee agreement. The California superior court held the fee agreement unenforceable on the ground that Birbrower had participated in the unauthorized practice of law. Birbrower appealed, and the state appellate court upheld the superior court decision. Birbrower petitioned the Supreme Court of California for review.