Ministers intend to abolish England's district and borough councils and put larger combined authorities in their place, most of them under a mayor, each promised more say over how money is spent and more power to unlock growth.
Under current plans the Borough of Swindon would be included in a Thames Valley authority. Some council leaders in Berkshire and Oxfordshire do not want it there, arguing that the geography does not work.
The leader of Swindon Borough Council, the Conservative Gary Sumner, put it less technically. "It's like not being invited to the party with the popular kids," he said.
The leader of Oxfordshire County Council, the Liberal Democrat Tim Bearder, was more direct. "With no offence to my friends in Wiltshire, you are not in the Thames Valley," he said.
Sumner's case for inclusion is economic. "Swindon is a vast economic powerhouse in a potential Thames Valley devolution deal," he said. "This is about coming together for growth we can pitch for infrastructure funds that can unlock investment in our town centre."
He also argued that Swindon could help rural Oxfordshire councils reach a housing target under the spatial development strategy by allocating more land in its town centre. "Oxfordshire don't want their green fields covered in houses," he said. "We've got brownfield sites that could deliver thousands and thousands of homes, at pace."
Bearder did not accept the trade. "It is not something you can use as a bargaining chip to get into a Mayoral authority," he said. On Swindon's inclusion he said he did not think it was a good fit, adding: "You would have to rearrange all the boundaries."
There are practical arguments too. Under combined authorities, mayors and deputy mayors would also oversee services such as police and fire. Swindon's currently operate within Wiltshire. "It makes sense to have the set-up with Swindon staying in Wiltshire," Bearder said.
Not everyone in the proposed authority agrees with him. The Labour leader of Oxford City Council, Susan Brown, said it was "vital" that Swindon was part of the Thames Valley. "We're incredibly closely connected in terms of our economies," she said.
Windsor and Maidenhead's leaders objected to the most recent plans on a separate point, partly because a Foundation Strategic Authority was being proposed rather than one run by a mayor.
Wiltshire Council's own leaders, meanwhile, are looking to form a Wessex Mayoral Authority with nearby Somerset, Dorset, and Bournemouth, Christchurch and Poole. There are also discussions about whether Buckinghamshire and Milton Keynes would be part of the same group.
For a plan to be submitted to government it needs approval from all parties across the affected councils. "It has to be unanimous and I will only do that when it is right," Bearder said. Elsewhere in the country, local government reorganisation has been paused.
It is worth separating the two questions on the table, because only one of them is administrative. The first is which councils should share a mayor. The second is whether Swindon is in the Thames Valley.
On the second, the position is now unusually clear. Swindon's location is a matter for consultation. The town will be in the Thames Valley if, and only if, every affected council agrees that it is, and the agreement has to be unanimous.
This newspaper regards that as a considerable advance on conventional geography, which has never required sign-off. Valleys and catchments have until now been settled by water, which cannot be lobbied and does not attend meetings.
The mechanism for dissent is equally sound. Should the councils decline to admit the town, one leader has already identified the remedy: the boundaries would have to be rearranged. The valley moves. Swindon stays where it is.
Wiltshire's alternative settles the principle. Swindon's own county is proposing a Wessex authority with Somerset, Dorset and the Bournemouth, Christchurch and Poole area, a region that has not so far refused it. The Department of Unnecessary Research has therefore asked which body should be formally consulted on whether a valley contains a town. The list of affected councils runs to several. The river is not on it.