Just in time for the summer dining season, the U.S. government has given its blessing to restaurants that want to allow pet dogs in their outdoor spaces.

But even though nearly half of states already allow canine dining outdoors, the issue is far from settled, with many diners and restaurants pushing back against the increasing presence of pooches.

Restaurants have been required to allow service dogs for decades. But it wasn’t until the mid-2000’s that a handful of states — including Florida and Illinois — began passing laws allowing dogs in outdoor dining spaces, according to the Animal Legal and Historical Center at Michigan State University. Twenty-three states now have such laws or regulations.

But the legal landscape is confusing. Michigan law doesn’t allow dogs in outdoor dining spaces, for example, but lets restaurants apply for a variance from their county health department.