Urban rehabilitation is a public concern in an epoch of very scarce public means. Partnering with private real estate development (RED), reducing or eliminating public investment and maximizing positive externalities, is a must for urban authorities. How can RED fit this rationale with good private business outcomes? Speculative RED normally targets the average end-user of the market range it addresses. This goes against the variability and the specificity that RED in urban rehabilitation commonly imposes and which brings with it accrued risk, requiring a very detailed business approach that has to be combined with the management of the legal contexts on the public side.The present importance of urban rehabilitation for the RED business derives mostly from reduced business margins elsewhere, either because sustainability makes land development very expensive or impossible, or because new lifestyles reduced willingness to pay for peripheral locations. Tourism development, which is an important business domain for RED in Portugal, has met its ceiling as far as end-user purchase demand is concerned. Urban rehabilitation is therefore a privileged business area for both RED and urban authorities, where state of the art RED resides.Finding out what are the components of a RED detailed approach to urban rehabilitation and its relationship with the urban authorities is the aim of the paper, through a much talked about case study in Lisbon.