Background: Turning is the most important trigger for freezing of gait (FOG) in Parkinson's disease (PD), and dual‐tasking has been suggested to influence FOG as well. Objective: To understand the effects of dual tasking and turning on FOG. Methods: 14 Freezers and 14 non‐freezers matched for disease severity and 14 age‐matched controls were asked to turn 180° and 360° with and without a cognitive dual‐task during the off‐period of the medication cycle. Total number of steps, duration, cadence, freezing‐frequency, and secondary‐task performance were measured. Results: Seven freezers froze during the protocol. Freezing occurred in 37.5% of trials during 180° turning compared to 0% during straight‐line walking (X² = 10.44, p < 0.01). The occurrence of FOG increased during 360° when also a dual‐task was added (X² = 4.23, p = 0.04). Freezers took significantly more steps and were slower than controls in all conditions. The presence of a dual‐task increased these differences. Cadence increased significantly for freezers during 360° and 180° compared to straight‐line walking. In contrast, cadence was decreased during turning in controls and non‐freezers. During straight‐line walking, only freezers made errors in the secondary task. Controls increased their error‐rate during 180° turning, whereas freezers deteriorated their secondary task performance during 360°. Conclusions: 360° turning in combination with a dual‐task is the most important trigger for freezing. During turning, non‐freezers and controls decreased their cadence whereas freezers increased it, which may be related to FOG. Freezers adopted a posture second strategy in contrast to non‐freezers when confronted with a dual task. © 2010 Movement Disorder Society