The agency will be working with the Standard to support the paper's in-house corporate affairs team on all its London activity and trade PR.
Braben director Vicky Hurley leads an account team of three, reporting to the office of MD Sally De La Bedoyere at the Standard.
The Standard has been undergoing a major editorial shake-up over the past two months following the resignation of editor Max Hastings and appointment of his replacement Veronica Wadley, formerly deputy features editor at stablemate Daily Mail.
Hastings had been with the paper for over six years. When he joined, the Standard's daily circulation stood at 522,000, but had dropped to under 400,000 earlier this year.
Last month, the overall parent group Daily Mail and General Trust warned ad rates would continue to remain depressed this year.