Successful layering starts with what you put next to your skin whether that's a natural fibre like Merino Wool or a synthetic fibre. IceBreaker, SmartWool and Mons Royale merino wool continue to be popular as they are soft and warm and guaranteed to be anti-odour. The great thing about merino wool is that when a lot of synthetic fibres will start to smell after a day or two of use you can wear merino wool for days and days without any odour. If you want to go down the synthetic route then North Face, Odlo, Arcteryx and Norrona produce a great range of styles. Here at LD Mountain Centre we have merino wool and synthetic base layers in various warmth ratings with zip or crew neck and long or short sleeve and full or 3/4 length bottoms, we even have some onesies!