The purpose of this study was to assess quality of life (QoL) of patients with idiopathic Parkinson's disease (IPD). The Parkinson's Disease Questionnaire (PDQ-39) was compared with an individualized QoL tool: the Schedule for Evaluation of Individual Quality of Life Direct Weighting (SEIQoL-DW). One hundred twenty-three patients underwent interviews using these tools, together with the Mini Mental State examination, Beck Depression Inventory, a qualitative pain assessment, and the Palliative Care Assessment tool (for symptoms). The SEIQoL-DW was well tolerated and demonstrated that QoL not only was broad and highly individualistic but also was determined more by psychosocial than physical issues. Of the 87 domains nominated by patients, the most common were family (87.8%), health (52.8%), leisure activities (36.6%), marriage (35%), and friends (30.9%). The SEIQoL index score was predicted by depression but not by disease stage. However, the PDQ-39 was predicted by disease stage, the number of symptoms, and depression. Direct comparison of the tools confirmed that the SEIQoL index score was predicted by the PDQ-39 domains of social support, cognitive impairment, and emotion. The use of the SEIQoL-DW challenges current thinking within IPD research regarding QoL and its assessment using the PDQ-39.