Like most forms of testosterone in the US and North America, it is only legal to buy Sustanon with a prescription from your doctor. Due to its long-estered formula, many physicians actually prefer it to other versions of the hormone because it requires fewer office visits and more convenience. As such, it is often easier to find this product in the underground market simply because it is widely available. On the other hand, the purchase, possession, and use of Sustanon are illegal without a prescription. Before you buy Sustanon, make sure you understand the potential legal implications.