In order to proceed with exploring the methodological issues related to the measurement (indicators of happiness) and evaluation (quality of happiness), it is important to clarify what we mean by the term ‘happiness’. The debate around the definition of a new approach of measuring well-being of nations has put ‘happiness’ at the centre of concerns by highlighting, among others, two aspects to be considered: the individual observation and the subjective dimension. The necessity to consider the individual perspective, completely ignored by the traditional GDP approach, in measuring countries’ well-being is broadly urged and accepted. Many point out that the most important dimension of the individual perspective is represented by the subjective perception, defined in terms of happiness. However, focusing on the individual perspective, especially if that is done exclusively on a subjective perception, is affected by some risk. This contribution aims at exploring the conceptual issues related to those risks, which refer to some dualisms around well-being (subjective vs. objective, happiness vs. subjective experience, individual vs. community, present vs. future). These issues are important in order to define the indicators able to monitor happiness and to support its quality assessment.