If the defendant's forum state contacts are continuous and systematic, jurisdiction will exist when the nature of the contacts gives rise to the cause of action. General jurisdiction is also proper for causes of action wholly unrelated to the nature of the contacts if the defendant's contacts are continuous and systematic. However, jurisdiction is improper if the defendant's contacts are casual or sporadic and unrelated to the cause of action; "it is essential in each case that there be some act by which the defendant purposefully avails itself of the privilege of conducting activities within the forum state, thus invoking the benefits and protections of its laws." Sporadic activity, even a single act, may yield jurisdiction where the cause of action is directly related to the activity as in McGee v. International Life Ins. Co., 355 U.S. 220 (1957) According to McGee, mailing a single insurance policy to a policyholder in the forum state yielded "substantial connection" such that specific jurisdiction in the forum state was proper for a suit arising out of that policy.

Subsequent decisions have refined the minimum-contacts test by examining the foreseeability of litigation in the forum state to determine if the defendant "should have reasonably expected being haled into court there," given the nature and substance of his contacts. In World Wide Volkswagen Corp. v. Woodson, 444 U.S. 286, 297 (1980), the Court rejected jurisdiction as improper where a New York defendant's only contact with forum state Oklahoma was the sale of a vehicle in New York that was later driven to Oklahoma. The World Wide Volkswagen Court further asserted that the minimum contacts test is a threshold that must be reached before the court can evaluate "fair play and substantial justice."

In some cases involving intentional torts such as libel, the role of foreseeability in determining jurisdictional propriety is limited.

In Burger King Corp. v. Rudzewicz, 471 U.S. 462, 483 (1985), the Supreme Court further refined the minimum contacts test, holding that a long-term commercial relationship constituted a "deliberate affiliation with the forum" and thus the possibility of litigation in that context is reasonably foreseeable. Additionally, the Supreme Court held that even when minimum contacts are sufficient to confer jurisdiction to the forum state, jurisdiction must comply with "fair play and substantial justice" evaluated according to five factors: (1) the burden on defendant of litigating away from his or her home state; (2) the interests of the forum state; (3) the plaintiff's interest in obtaining relief; (4) the interest of the interstate judiciary in efficiently resolving disputes; and (5) shared interests in social policies.