Founded over 100 years ago, ADT Security Services, Inc. is the nation’s leading security company. ADT is trusted with helping protect millions of families, homes, and businesses. When you sign up for ADT monitoring, trained professionals with the most advanced security technology will be monitoring your home 24 hours a day, 7 days a week. As ADT invests in state-of-the-art security technology, your family will have the opportunity to benefit from advances like mobile control and remote video monitoring unlike anything available from other security companies.