In Buddhist thought, karma (kamma) is understood as intentional action of body, speech, and mind, governed by the law of cause and effect. The Buddha is recorded as defining karma specifically as intention, meaning that what truly carries karmic weight is not mere outward behavior but the volitional impulse behind it. Actions rooted in generosity, compassion, and wisdom are considered wholesome or skillful, while those driven by greed, hatred, and delusion are unwholesome or unskillful. These intentional actions leave subtle impressions, often described as karmic seeds, which shape character and future experience. Neutral actions, which lack strong moral charge, carry comparatively minimal karmic consequence.

Karma is not portrayed as a system of divine reward and punishment, but as a natural process by which intentional actions condition future states of mind and existence. The cumulative pattern of wholesome and unwholesome intentions influences both the quality of present experience and the trajectory of future lives. At death, the dominant karmic tendencies and especially powerful past actions help determine the next realm of existence. Traditional Buddhist cosmology describes multiple realms, including gods, demigods, humans, animals, hungry ghosts, and hell beings, and karma is said to shape not only which realm is entered but also the specific conditions encountered there, such as relative happiness or suffering.

This process unfolds without positing an eternal, unchanging soul; what continues is a causal stream of mental and karmic conditions moving from life to life. Unripened karmic seeds can carry forward across lifetimes until circumstances allow them to bear fruit, so that past intentions may manifest long after the original act. As long as actions rooted in greed, hatred, and delusion continue to generate fresh karma, beings remain bound within saṃsāra, the ongoing cycle of death and rebirth. Yet this is not strict fatalism: present choices and mindful conduct can reshape the karmic stream, even at the moment of death, and can gradually weaken the forces that perpetuate rebirth.

The Buddhist path of ethical conduct, meditation, and wisdom is presented as a way to transform and eventually exhaust the karmic forces that bind beings to cyclic existence. Wholesome intentions cultivate conditions for more favorable rebirths, such as human or heavenly realms, while unwholesome intentions tend toward painful states, such as animal, ghost, or hell realms. When greed, hatred, and delusion are fully uprooted, no new karma leading to future rebirth is produced. A fully awakened being may still experience the remaining results of past karma in this life, but with no further karmic accumulation, the cycle of rebirth comes to an end, and with it the suffering that arises from wandering in saṃsāra.