Resurrection

Resurrection is the process by which the deceased are returned to life through various external means.

Elixir of Life
The Sisterhood of Karn has been shown to be able to resurrect a Time Lord using their Elixir of Life. However, this is a temporary measure and only brings back the resurrected for a few minutes. Another dose of Elixir can be used to induce and control a regeneration, bringing the Time Lord back completely. (TV: The Night of the Doctor)

Bad Wolf entity
The Bad Wolf entity has shown the ability to resurrect the dead. However, as Rose Tyler didn't possess complete control over this power, she brought the person back forever. (TV: The Parting of the Ways, Utopia)

Time Lords
The Time Lords have been stated to have the ability to resurrect deceased Time Lords. (TV: The Sound of Drums)

Potions of Life
Before his Harold Saxon incarnation was killed, the Master detailed the "potions of life" to the Cult of Saxon in their Book of Saxon. Combined with the Master's ring and his biometric imprint, this was capable of resurrecting the Master even after cremation. However a "potion of death" could interrupt the resurrection and make it go wrong. (TV: The End of Time)

The Doctor
After being killed when Cass' ship crashed on Karn, the Eighth Doctor was resurrected by the Sisterhood of Karn with the Elixir of Life as the Sisterhood saw the Doctor as the only chance to stop the Last Great Time War. This resurrection was only temporary and would only last about four minutes, but the Sisterhood offered to use the Elixir to induce and control a regeneration for the Doctor, bringing him back fully. The Doctor ultimately chose to regenerate into "a warrior." (TV: The Night of the Doctor)

The Master
After falling into the Eye of Harmony, the Master was resurrected by the Time Lords to fight in the Last Great Time War. (TV: Doctor Who, The Sound of Drums)

After being killed by Lucy Saxon and cremated, the Cult of Saxon took the Master's ring and used it, the "potions of life" and the biometric imprint left upon Lucy's lips by the Master's kiss to resurrect him. As part of his resurrection, the Master began drawing the life force from the cult. However, Lucy countered this with a "potion of death" that interrupted the Master's resurrection and created an explosion that destroyed the prison. The Master survived, but was left with a degenerating body, a ravenous appetite, an even more deranged personality and the ability to fire energy bolts from his hands. (TV: The End of Time) The Time Lords were later able to repair these problems, fully restoring the Master. (TV: The Doctor Falls)

Jack Harkness
After being killed by the Daleks on Game Station, Jack was resurrected by Rose Tyler as the Bad Wolf entity. (TV: The Parting of the Ways) However, Rose could not control the power and instead brought Jack back forever. This resulted in Jack constantly coming back to life after each time he died. The Doctor was unable to fix this and was unsure if Jack would ever permanently die or not. (TV: Utopia, Last of the Time Lords)

Rory Williams
The Eleventh Doctor's companion Rory Williams had a habit of dying and coming back to life in various ways.

Rory first died when he took a blast from a Silurian for the Doctor and died. He was subsequently erased by a Crack. (TV: Cold Blood) Rory eventually returned as an Auton duplicate, but with the memories and personality of the real Rory. After the Big Bang Two, the original Rory was fully restored. (TV: The Pandorica Opens, The Big Bang)

Rory later drowned, but was revived by Amy Pond through CPR. (TV: The Curse of the Black Spot)

After being sent back in time by a Weeping Angel, an elderly Rory from an alternate timeline died in a room in Winter Quay. To prevent this, Rory and Amy jumped off of Winter Quay, killing them both but negating this timeline and bringing them both back. Before jumping off the roof, Rory referred to his many resurrections by responding "when don't I" when asked if he thought he would just come back to life. (TV: The Angels Take Manhattan)