This paper considers the agency and influence of planning processes and densification policies on urban landscapes in London. Urban transformation through residential densification can bring opportunities for real estate development, combined with longer term investment and financial gains for local authorities through planning gain. However, the measurements and indicators used to define density and its impacts could be better understood both objectively and subjectively through the lens of an extended notion of ‘value’. Such experiences of density can be viewed bluntly as positive or negative. This research investigates nuanced dimensions of density and adopts a primarily qualitative approach, reflecting on relevant literature and wider policy context through a discourse analysis relating to densification in London. The idea of elements of ‘value’ is explored and evaluated in ongoing developments through a detailed case study of Nine Elms, London. Quantitative data on the residential real estate market is used to illustrate investment flows. Conclusions consider best practice policy recommendations in relation to understandings of ‘value’. 'Policy relevance' Lessons from London indicate how densification can be a viable option for both urban policy makers and practitioners when approaches adopt a flexible governance and planning approach, embedded in local context. Densification processes in planning and governance should be regularly reviewed and reconsidered in line with broader national and city-wide policies, optimising rather than maximising density. Both subjective and objective measurements should be accounted for, by reflecting on broad and informed indicators. The value created by densification processes should be the result of a weighted and broader assessment of variables: economic, social, and place-specific considerations. However, the often antagonistic, ambiguous nature of density and its application needs to be recognised by policy makers, regulators and actively involved parties (planners, developers, investors) to contribute to the creation of successful places.