Stop me if you’ve heard this one: a man walks into a bar after seeing a TV ad… but there’s no way for the advertiser to prove it ever happened.

On Tuesday, TV data company Alphonso inked a partnership with PlaceIQ to use the latter’s location data as a bridge between sitting on the sofa and walking through the door. 

Linking TV exposure to visitation is a perennial challenge for advertisers and now, increasingly, for networks, which are starting to sell campaigns based on outcome guarantees, said Raghu Kodige, Alphonso’s chief product officer and co-founder.