This project will create a catalogue of all the sexual orientation, mental health and psychological well-being questions asked across the CLOSER particiption studies. Sexual orientation includes self-identification, romantic attraction and sexual behaviour and different studies measure each of these differently. How sexual orientation is measured may influence how analytical findings are interpreted or policy implications taken from those findings.Similarly, mental health and psychological well-being also cover a variety of topics including happiness, life satisfaction, anxiety and depression. The measures used by studies might also influence the interpretation of findings and policy implications. We will conduct analyses that examine the relationship between sexual orientation and different measures of mental health and psychological well-being. We will also look at this relationship among individuals who report changes to their sexual orientation.