The Dharma Initiative was a scientific group who came to the island in the mid 60's to research all the strange properties there. Unlike the others who see all the strange happenings of the island as spiritual or supernatural the dharma initiative believe their are scientific reasons for why certain energies exist there and why some laws of the universe don't seem to apply. The dharma initiative has set up many stations around the island, each for a unique purpose that is revealed as the survivors discover them. The Dharma Initiative was in a type of cold war with the hostiles where neither side seemed to make a move, until the "purge" happened years later which killed off most of the dharma members with poison gas. The only 2 members that didn't die were Ethan and Ben who joined the others group.
*WARNING - THE FOLLOWING INFORMATION MAY CONTAIN SPOILERS IF YOU ARE NOT CAUGHT UP IN THE SHOW.
Alvar Hanso - The creator of the dharma initiative. Although not seen on the show he has been mentioned by the dharma members frequently and can be seen on some of the online promotional videos for lost.
Horace Goodspeed - Horace was a mathematician and the leader of the dharma initiative the entire time that it operated on the island. He was also the father of Ethan which years later turned out to switch sides and join the others.
Pierre Chang - Pierre is one of the main scientists on the island and does the instructional videos for each of the dharma stations initiates. In the videos he goes by the alias's Marvin Candle, Mark Wickbund and Edgar Halliwax but the reason for these fake names in unknown. He seems to know the most about the scientific reasons for the strange properties of the island and is often the first one called if their is a problem at one of the stations. He is later revealed to be the father of Miles Straum.
Stuart Radzinsky - Radzinsky is the paranoid head of research for the dharma initiative. He Designed one of the dharma stations, the swan, which he later worked at for years until the pressure got too much for him and he killed himself.
Roger Linus - Ben's father and the reason Ben arrives on the island in the first place. Roger comes to the island to work only to discover that the only job he qualifies for is a janitor. Roger is an alcoholic who physically and psychologically abuses Ben by hitting him and blaming him for causing his mothers death during childbirth. He is the first one that Ben kills during the purge.