As a private investigator the polygraph is an excellent aid to have, I have found over the years that more and more clients require their partners tested. This is probably due to the fact that more and more TV shows use it and the public are more aware it is available to everyone and not out of their reach.  

So you need to ask the question?

Is Your Spouse or Significant Other Cheating? Are there questions in your relationship that remain unanswered? When the trust is lost or in question in a relationship, it could take years to recover, if ever. In most cases, the evidence of INFIDELITY is not definitive.

The only way to find out the truth is through a polygraph/lie detector test. Polygraph tests have been used extensively in relationship issues. This is one area of testing where experience makes a big difference. The wording of test questions is critical to achieve a successful exam; different people interpret words differently. This format is used to determine whether one partner has been intimately/sexually involved with someone other than his or her partner. Included in this format may be questions about dating, kissing, and physical contact with others.

What else can we test for?

Personal History

This specific format is appropriate when a partner needs to verify aspects of his/her partner's background, such as sexual history, drug or alcohol habits, gambling, health issues (particularly STD's), and excessive financial obligations.

Internet Activities                        

Not all "cheating" requires physical contact. Polygraph can be used to determine the extent of "sexual" activities conducted over the internet, such as visits to pornographic sites, dating sites, visits to sexual chat rooms, interactive sexual web sites, or having "cybersex" (sexual chat) with someone who is not his/her partner. The polygraph test can also be used whenever truth is needed for example- Pre-employment screening, sexual abuse concerns, theft to drugs abuse, family disputes etc.

Personal Theft Issues

Parents use Polygraph testing as an investigative tool, to aid in determining the truth when family members, children or acquaintances have fallen under suspicion to be involvement or knowledge in recent thefts, embezzlement, vandalism, of personnel property.

Employment Theft Issues

Polygraph Exams are used by many employers as an investigative tool, to aid in determining whether, or not employees had any involvement or knowledge in recent thefts, embezzlement, vandalism, or misappropriations of company funds or property.

So now you have all the information about polygraph testing, use it, it's not just for peace of mind