Mosses are a major component of the vegetation in ice-free coastal regions of Antarctica. They play an important role in the colonisation of ice-free terrain, accumulation of organic matter, release of organic exudates, and also provide a food and habitat resource for invertebrates. They serve as model organisms for physiological experiments designed to elucidate problems of plant cold tolerance and survival mechanisms and for monitoring biological responses to climate change. This Flora provides the first comprehensive description, with keys, of all known species and varieties of moss in the Antarctic biome. It has involved microscopic examination of around 10,000 specimens from Antarctica and, for comparison, from other continents. All species are illustrated by detailed line drawings, alongside information about their reproductive status, ecology, and distribution. This is an invaluable resource for bryologists worldwide, as well as to Antarctic botanists and other terrestrial biologists.

Ryszard Ochyra is Head of the Laboratory of Bryology at the Institute of Botany, Polish Academy of Sciences in Krakow. He has undertaken fieldwork in Tanzania, South Africa, Antarctica, Tierra del Fuego, the Falkland Islands, Prince Edward Islands, Iles Crozet and Iles Kerguelen. He has received numerous awards including the prize from the Prime Minister of the Polish Government in 2000 for outstanding scientific achievement.

Ronald I. Lewis-Smith joined the British Antarctic Survey in 1964 as a cryptogamic ecologist, and in 1975 he was appointed as head of the BAS Plant Biology Section. He worked extensively throughout South Georgia, South Orkney and South Shetland Islands, and the Antarctic Peninsula and continental Antarctica, before retiring from BAS in 2002. He was awarded the British Polar Medal in 1977 and a clasp in 2002 in recognition of his contribution to Antarctic science.

Halina Bednarek-Ochyra is based at the Institute of Botany, Polish Academy of Sciences in Krakow, where she became Curator of the Bryophyte Herbarium in 1993. She is a skilled botanical illustrator, and in 1996 and 2004 was awarded a prize by the Second Division of the Polish Academy of Sciences for outstanding scientific achievements.