Be sensitive. They operate in different markets, and you can't fit a square peg in a round hole. Imposing centrally formulated rules may be unhelpful.
Listen. They're the local experts: where their market is concerned, they may know better than you. Would their know-how work in your other markets? Ask them to present to head office and counterparts in other regions.
Keep an eye on things. Make sure they don't confuse distance with the right to do as they please. It's not the Wild West out there.
Treat them as equals. Give them the same conditions as head-office staff. Working in a far-flung outpost of the empire shouldn't mean shabby offices or fewer benefits. Where benefits aren't transferable, find alternatives.
Involve them. Encourage visits to head office. Include them in central training and introduce them to key people within services departments. Have new staff attend inductions with colleagues from different regions. And invite them to the head office Christmas party.
Spread the love. Encourage staff to apply for positions in other offices. Let them move from region to region, taking their expertise with them. Just make sure that some are happy to choose Bolton over Barcelona.