Sources in government were delighted that she visibly forced out a 100% commitment from him to Nato, the more experienced politician perhaps, the formal, next to the flash.
The relationship between any prime minister and any president is always important. But with Britain stepping back from its European ties, the bonds across the Atlantic become only more vital.
Theresa May's presence seemed to bring out a more restrained Donald Trump. Could she be building an image, a role, as a good influence on the rogue president?
This is a high wire act. For hitching her own political fortunes to President Trump, praising his "stunning victory", gambles that he will not crash and burn as president, gambles that those concerned about his beliefs at home, will not be repelled by her overtures to the new leader.
Only a perverse British prime minister would not try to build a good relationship with an American leader. But Theresa May's host is a new kind of president. The pressure this new political friendship could put on her will be new too.
If they wanted to display closeness - the image of Theresa May hand in hand with Donald Trump could hardly have been more useful for Downing Street.