When compared to urine, hair analysis has a much larger window of detection, ranging from weeks to months, depending on the length of the hair shaft. The results of a hair test provide information dealing with long-term drug exposure, although it has been demonstrated for some drugs that a single exposure is detectable in hair. With respect to doping agents, the Society of Hair Testing has published in 1999, a consensus opinion but hair analysis is not recognized by the World Anti-Doping Agency (WADA). Nevertheless, the Court of Arbitration in Sports has recently accepted several reports presenting data based on hair analysis. In case of an adverse analytical finding, hair testing can be a complement to document the claim of the athlete but of course, the result should not be considered as an alternative to urinalysis. This is because a negative hair result cannot exclude the use of the detected drug and cannot overrule the urine result. In the recent months, this laboratory was requested to test for ligandrol (LGD-4033) and ostarine (S-22 or MK-2866) in 2 different doping cases, detected at very low concentrations in urine. Both drugs are selective androgen receptor modulators (SARMs) which are prohibited by WADA at-all-times under section S1.2 of the list. Ligandrol, ostarine and andarine (S-4) are the most abused SARMs and are only available through the Internet suppliers, even for analytical toxicologists, and are not approved for human use. SARMs identification has never been reported in hair. Drugs were extracted from hair after decontamination under mild alkaline condition and submitted to LC-MS/MS. In case 1, ligandrol was not detected in hair, suggesting possible contamination by a supplement taken by the athlete. In case 2, ostarine tested positive in the 2×3cm hair segments at approximately 12 and 138pg/mg. Confirmation was obtained by LC-HRMS. The difficulties in interpreting these data are discussed, in the light of the lack of controlled studies in the literature.