The prevalence of obesity with comorbid binge eating behaviour is growing at a faster rate than that seen for either obesity or eating disorders as separate conditions. Approximately 6% of the population are affected and they potentially face a lifetime of poor physical and mental health outcomes and an inability to sustain long-term weight loss. Current treatment options are inadequate in that they typically address either obesity or eating disorders exclusively, not the combination of both conditions. By treating one condition without treating the other, relapse is common, and patients are often left disappointed with their lack of weight loss. An integrated approach to treating these individuals is needed to prevent a worsening of the comorbidities associated with excess body weight and eating disorders. A new therapy has recently been developed, named HAPIFED, which addresses both overweight/obesity and comorbid binge eating behaviour with the combination of behavioural weight loss therapy and cognitive behaviour therapy-enhanced (CBT-E). The aim of this paper is to document the protocol for the Real Happy Study, which will evaluate the effectiveness of the HAPIFED program in treating overweight or obesity with comorbid binge-eating behaviour in a real-world setting.