Globally, the prevalence of those living with obesity (≥30 kg/m2) is rising, with this trend expected to continue if firm and decisive policy interventions are not introduced. Across Europe, despite many consecutive policies aiming to reverse rising trends in weight status over recent decades, no country is currently on track to halt and reverse current trends in the coming years. This is evident in Ireland too, whereby the reporting of nationally representative weight status data show that targets have not been achieved since reporting began. The aim of this review is to critically appraise recent evidence relating to the key determinants of obesity including weight status, diet quality and physical activity with an emphasis on socioeconomic inequalities. And to consider these in the context of respective policy measures and propose future-focused recommendations. Furthermore, as with the complex nature of obesity, multifaceted approaches that shift the focus from the individual and place responsibility at a societal level will be reviewed.