The timing of puberty has considerable biological, psychosocial and long-term health implications. Secular trends in age at pubertal development, the effects of obesity and the potential effects of environmental endocrine disruptors challenge the standard definitions of precocious puberty and the indications for intervention with gonadotropin-releasing hormone agonists (GnRHa) in girls with precocious puberty. GnRHa therapy is effective in improving adult height in patients who present with classic central precocious puberty (at <8 years old), without causing adverse effects on body composition, BMD and reproductive function. However, its benefits in patients with atypical forms of early puberty not driven by luteinising hormone are not well defined. The role of GnRHa in these patients and the potential benefits in terms of later growth, psychosocial functioning and long-term risk of adult diseases that are associated with early menarche, such as breast cancer and the metabolic syndrome, have not been established.