Initiating treatment of osteoporosis is important. However, long-term adherence to treatment of osteoporosis is very poor, with most discontinuation or erratic intake of medication observed during the first few months. Our objective is to maintain observance (i.e. intake of at least 80% of the doses of drugs according to patient questionnaires and to delivery of drugs by pharmacists) at one year in at least 80% of the patients who have initiated treatment. To that end, we will also evaluate whether disclosure of the results of measurements of blood markers of bone metabolism will influence patient adherence to treatment over time. The correlation of these measurements with results of phone follow up interviews and drug delivery by pharmacists as indicators of adherence will also be determined.