The Perfect... Baselayer

Wicking... The perfect base layer should wick like a demon because its primary job is to transmit moisture away from your perspiring skin and off to either your wicking mid-layer and / or your breathable shell and thence to the outside world. In our experience, thinner base layers wick better than thicker and all things being equal we'd opt for thin every time. Leave the insulation to your mid-layers.

Non deteriorating... Base layers work in either of two main ways - through the physical structure of the fabric like, say Powerdry or Lowe's Dryflo, which means the effect won't wear off, or through a treatment applied to the fabric (Patagonia's Capilene for example.

Close fitting and comfortable The closer fitting your baselayer, the greater its contact with your skin and the better it should be able to wick. Loose may look better or be more comfortable in summer, but for ultimate wicking performance, close-fitting is best. We also find that some fabrics have a slightly slick, shiny feel that while it may not have an impact on overall perforamance, doesn't feel as nice against the skin - Berghaus ABL and ME's new baselayer for example.

Comfortable hot or coldIt's hard to manage comfort in both hot and cold conditions. Merino wool is one answer that seems to work reasonably well, others are more high tech like the Lowe Alpine Dri Zone that places extra thin wicking panels over hot spots on the body. Like we said before, it's our experience that thinner baselayers wick most effectively and we'd leave the insulating to the mid-layers.

Non Pong There's nowt worse than a stinking base layer and Helly's old Lifa, the infamous 'Smelly Helly' was the best known - the latest Lifa, by the way, doesn't niff. The latest answer is fabric which incorporates silver threads or fibres. These are anti-bacteriological and kill off the bacteria which produce smells. In our experience the treatment works well.

Cheap as chips You wish... Except that we have it on good authority that one of the best-performing baselayers comes straight from the own brand range of a well known outdoors store. Bear in mind that big companies buy in fabrics from different suppliers and you could find the same fabric under different labels at different prices. And like we said, virtually anything is better than a cotton tee...

Construction Our general cut of choice is long sleeved with a collar and a deep zip neck for ventilation when the going gets hot. The collar is comfortable and helps protect the back of the neck from sun and you can always roll the sleeves up if you're warm. Make sure the zip doesn't rub against your skin though.

Black... Only one colour for baselayers, erm, black. Actually although black may look cool, it's not such a good idea in certain situations. On glaciers during the day, for example, the reflective properties of white baselayers make them much better than heat absorbing, oven-ready darker shades... So white is the new black. Erm, sort of.