International Shoe Corporations defense was not valid. A courts exercise of personal jurisdiction is constitutional when a defendant has minimum contacts with the state where a lawsuit is brought such that notions of fair play and substantial justice would not be offended. For the purposes of personal jurisdiction, a corporation is normally subject to the jurisdiction in the state in which is was incorporated, has its principal office and is doing business. Under the long arm statute, a court can exercise jurisdiction over certain out-of-state activities that took place within the state. In this case, International Shoe was doing business in Washington--it had minimum contacts through the 11-13 salespersons it had in Washington who exhibited samples and solicited orders from customers in the state on a systematic and continuous basis.