Mayor Nutter's decision to conduct a forensic audit of the Neighborhood Transformation Initiative provides a welcome opportunity to assess a program that costs too much and has failed to deliver on its promise.

It was always hard to get a handle on NTI's performance when its creator, John Street, was mayor. Street was always quick to recount the good things that NTI had done but was loath to discuss the agency's shortcomings.

Nutter is acting in the wake of questionable accounting practices involving NTI that were recently discovered. It appears that money used to acquire distressed properties was being drawn improperly from a specific fund.

The mangled accounting involved the city's overburdened Redevelopment Authority, which actually carries out the condemnation of properties tagged for demolition by NTI. The authority's chairman since 2000, union leader John J. Dougherty, quit that post last month.

NTI, though, deserves scrutiny beyond an examination of whether some land acquisition costs were improperly paid. The program has never lived up to the high expectations Street voiced when he announced it in 2001.

Street set a five-year goal for NTI to demolish 14,000 derelict buildings. But by the end of 2007, fewer than 8,000 had been taken down - at a cost of $181 million. Ed Rendell demolished 10,813 buildings at a cost of $88 million when he was mayor.

NTI deserves props for replacing many rundown properties with attractive green space that may one day beckon developers. But many Philadelphia neighborhoods are still marred by abandoned buildings that stick out like sore thumbs between vacant lots.

Nutter should take this opportunity to decide whether NTI should be revamped or replaced. In his assessment, he needs to determine if there is a better way to accomplish what NTI has done in working with community organizations to redevelop condemned properties.

Street was right seven years ago to aggressively seek to rid the city of dangerous, blighted properties and replace them with attractive housing and other amenities that make communities liveable. But NTI's spotty record damns Street's decision to fund the effort with $296 million in bonds.

Philadelphia doesn't want to go back to the old way it handled condemnations and demolition. Before NTI, the city had amassed more than 26,000 abandoned properties, the most per capita of any city in the nation at the time.

But NTI's method isn't good for the city either. Its attempt to be an economic development engine has been costly, and the benefits have not been widespread. Starting with this forensic audit, Nutter, working with City Council, housing advocates, developers and other concerned parties, needs to come up with a better way.