The Right Sort of Man by Allison Montclair

 The setting is after WW2 in London. Our two heroines, Iris and Gwen (friends from vastly different backgrounds) decide to open a marriage bureau to help the lovelorn find mates. Unfortunately for them, one match that they arrange goes badly awry. The girl is found murdered in an alley and her date is arrested. He swears she cancelled the date before it happened so he never got to meet her--and the women of the marriage bureau decide to prove his innocence and hopefully find the real killer. It's a compelling story with 2 likeable heroines. And the start of a series, which I can't wait to read the next volume of.