This paper reports on analysis of active travel interventions in Outer London. We find stronger impacts of effects (decreased car ownership and use, increased active travel) in intervention areas where Low Traffic Neighbourhoods (LTNs) were introduced. Decreased car ownership and use is only found in such areas. Sample size for LTN areas is small and hence uncertainty about effect magnitude is large, but effect direction is consistent. This suggests that to reduce car use as well as increase active travel, LTNs are an important part of the intervention toolbox.