Spok Holdings, Inc., through its subsidiary, Spok, Inc., provides various communications solutions in the United States, Europe, Canada, Australia, Asia, and the Middle East. The company provides one-way messaging, including numeric messaging services, which enable subscribers to receive messages comprising numbers, such as phone numbers; and alphanumeric messages, including numbers and letters that enable subscribers to receive text messages. It also offers two-way messaging services that enable subscribers to send and receive messages to and from other wireless messaging devices, such as pagers, personal digital assistants, and personal computers; and voice mail, personalized greeting, message storage and retrieval, and equipment loss and/or maintenance protection to one-way and two-way messaging subscribers. In addition, the company develops, sells, and supports enterprise-wide systems to automate, centralize, and standardize clinical communications for contact centers, clinical alerting and notification, mobile communications, and messaging, as well as for public safety notifications. Further, it sells devices to resellers who lease or resell them to their subscribers; ancillary services, such as voicemail and equipment loss or maintenance protection, as well as provides a suite of professional services. The company serves businesses, professionals, management personnel, medical personnel, field sales personnel and service forces, members of the construction industry and construction trades, real estate brokers and developers, sales and services organizations, specialty trade organizations, manufacturing organizations, and government agencies. The company was formerly known as USA Mobility, Inc. and changed its name to Spok Holdings, Inc. in July 2014. Spok Holdings, Inc. is headquartered in Springfield, Virginia.