This has not been a promising start to the summer for the high street and neighbourhood retailing. A wave of closures at established retailers, combined with news from the Local Data Company and PwC that 20 stores have closed every day this year, has put increasing pressure on Mary Portas to deliver on her high- profile review of high streets.

She will be wise to consider the poor management decisions, the rise of internet retailing, the prevailing squeeze on household incomes and the crucial loss of consumer confidence. Couple this with consumer concerns about issues such as parking, and it’s clear it is no easy task.

Despite all of these variables, however, there is an elephant in the room that must not be ignored. We currently have a planning policy that explicitly favours town centre first development, but year after year councils have granted planning permission to retail space out of town. Town centre investment never peaked above 40% of new retail floorspace, even when there was money available to invest. In 2012, no new town centre retail developments will open.

It is inevitable that out-of-town development draws trade out of town centres, so traditional high streets suffer at the expense of the big sheds. Almost one in six shops on the high street are closing their doors, while supermarkets continue in their goal to offer everything under one roof, competing viciously with each other as everyone else suffers.

Mary Portas’ appointment may have grabbed the headlines, but it’s the less media-friendly planning policy detail that really holds the key to healthy high streets. Government must ensure that the policy tools are in place, but it is councils that will deliver them. What Mary is likely to come to realise is that while the problems are national, the only real solutions are local.