Freezing is a well-known problem in Parkinson's disease (PD) and is characterized by an abrupt difficulty in starting or continuing rhythmic and repetitive movements. We utilized a questionnaire in order to assess the occurrence of the freezing gait phenomenon (FG) in a population of 100 consecutive PD patients. Our PD population included 70 males and 30 females, with a mean age of 61.1 +/- 9.1 years. Mean duration of PD was 6.5 +/- 4.0 years. 92/100 patients were under L-Dopa treatment. The FG phenomenon occurred in 60% of patients. It appeared on average 4.8 years after the beginning of PD; in 16% of the cases it was evident before starting L-Dopa treatment. FG was more frequent among female patients. There was no significant correlation between the occurrence of FG and the age of the patients; on the other hand, a significant correlation was found with the duration of the disease (p < 0.001). FG occurred more frequently in the subgroup of patients with the akinetic form (odds ratio: 3.05); whilst an opposite tendency was evident in the subgroup with the tremor predominant form (odds ratio: 0.29).