Abnormal uterine bleeding (AUB) is a common complaint that affects large numbers of women from puberty to menopause. It negatively affects health by causing anemia, and impacts the quality of life of women affected. AUB also has an economic impact for both women and society. Therefore, it should not be under- or overestimate and diagnosis, investigations and treatment should be proposed, taking into account the scientific data available in the current state of medical knowledge. Using the new terminology and etiologic classification of AUB is essential to communicate properly around the subject. The evaluation of the bleeding includes self-report and more objective methods. Work out should focus on diagnosing anemia and researching for causal factors. It is important to differentiate AUB caused by anatomical changes and functional causes, and the PALM-COIEN classification has been developed on that dichotomy. Investigations may include blood test, ultrasound, hysteroscopy and endometrial sampling is required in a certain number of situations. Treatment for AUB can be medical and/or surgical depending on the cause. Medical treatment is based on iron supplementation, hormonal and non-hormonal therapies. Surgical treatments include removal of a focal lesion, endometrial resection or destruction and hysterectomy. Age, desire for future pregnancy and etiology for AUB are key factors to consider before initiating a treatment. Treatment efficiency can be assessed using the same tools as pretherapeutic evaluation, and improvement of quality of life has now become the main goal for most international guidelines addressing the subject.