The law generally requires the best notice possible under the circumstances in order to render binding orders or judgments regarding a person or entity. This is why, subject to many exceptions, someone must be served with a lawsuit/summons personally. The summons is the means by which the defendant is subjected to the jurisdiction and judgment of the court. State ex rel. Illinois Farmers Ins. Co. v. Gallagher, 811 S.W.2d 353, 354 (Mo. 1991). The summons further serves to place the defendant on notice of an action filed against the defendant to enable the defendant to appear and defend the action. Hometown Lumber & Hardware, Inc. v. Koelling, 816 S.W.2d 914, 916 (Mo. 1991). Proper service must be accomplished before a court can obtain jurisdiction over the person/property of a defendant. Like with any right, though, a defendant can waive formal service through appropriate documentation. Based on these principles, however, it often occurs that a defendant willl know that a lawsuit has been filed and will avoid service to delay/defeat the litigation. In such circumstances, usually a private process server is appropriate (though more costly).
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