Welcome, ACI Customers Alarm Center (DBA Custom Security Systems, Ace Fire & Security Systems, Alarm Guard Security Systems, and Capital Alarm) is now part of the STANLEY Security family. We are committed to delivering proven and innovative security solutions that protect what matters most to you. If your business is moving, under new ownership, or you need to make a change to your services with STANLEY Security, please use our Change In Service form. To pay your bill, visit our Online Billing service. If you have a question regarding your invoice, please visit our Invoice Inquiry page. To learn more about one of our other security businesses including STANLEY Access Technologies (Automatic Doors), STANLEY Healthcare, Sonitrol, or Pacom, please visit our Security Businesses Page. Thank you for being a STANLEY Security customer.