at service

at (one's) service

Available to help or serve one. Here I am, resident file clerk at your service! How can help with this project?
See also: service
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

at someone's service

Fig. ready to help someone in any way. The count greeted me warmly and said, "Welcome to my home. Just let me know what you need. I'm at your service." The desk clerk said, "Good morning, madam. I'm at your service."
See also: service
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

at (someone's) service

Ready to help or be of use.
See also: service
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
Building on years of experience assuring high-quality services in 2G and 2.5G deployments, Wireless QoS Manager enables wireless carriers to quickly identify and isolate 2G, 2.5G and now 3G service problems across multinational networks, minimizing downtime, ensuring high quality of performance at service launch, and providing faster time to market for new value-added services.