Measuring Quality of Life (QOL) can be difficult due to its individual character. To explore the value of personalized QOL measurement for people with dementia, personalized versions of two dementia-specific QOL scales (Dementia quality of Life (DQoL) and Quaility of Life in Alzheimer's Disease (QoL-AD)) were constructed. This study investigated whether the personalized measures are more valid to detect variations in QOL than their standard versions for people with mild to moderate dementia, with sufficient internal consistency. Moreover, the relationship between the personalized QOL measures and severity of dementia was investigated. Finally, the study explored the differences between countries regarding the personalized overall QOL and differences in the importance of QOL domains. This explorative one-group design study used baseline data from the MEETINGDEM study into the implementation of the Meeting Centres Support Programme in Italy, Poland and the UK. The personalized versions of the DQoL and QoL-AD were reliable, but not more valid than their standard versions. No relationship between severity of dementia and personalized QOL was found. While no differences were found between countries for the overall QOL score, some QOL domains were valued differently: people with dementia from the UK rated self-esteem, mood, physical health, energy level and the ability to do chores around the house significantly less important than people from Italy and Poland. The personalized versions of the DQoL and QoL-AD may offer dementia care practice important insights into what domains contribute most to an individual's QOL.