The analysis begins with an examination of Ninth Circuit Court of Appeals criminal cases involving trained dogs. The U.S. Supreme Court's dealing with the issue has been limited, so it is discussed within the context of Ninth Circuit decisions relying upon it. Civil cases involving drug-detecting dogs are also examined to determine parameters for their use. The analysis indicates the general rule is that a canine sniff is not a search when an inanimate object is involved. The fourth amendment, therefore, does not limit such investigations. If the object must first be removed from the possession of its owner, however, that removal is a seizure, and the seizure, not the sniff, must be based on reasonable suspicion. The use of a trained dog to examine a person, on the other hand, is a search, because the sniff may invade other privacy interests than simply the information retrieved. This may include embarrassment and inconvenience. The sniff of a person is equated with a 'Terry-stop' and requires reasonable suspicion. 131 footnotes.