A New Year's resolution is a commitment that an individual makes to a project or the reforming of a habit, often a lifestyle change that is generally interpreted as advantageous. The name comes from the fact that these commitments normally go into effect on New Year's Day and remain until fulfilled or abandoned. More socio-centric examples include resolutions to donate to the poor more often, to become more assertive, or to become more economically or environmentally responsible. People may act similarly during the Christian fasting period of Lent, though the motive behind this holiday is more of sacrifice than of responsibility. The new year resolution is one example of the rolling forecast-method of planning. According to this method, plans are established at regular short or medium-term time intervals, when only a rough long-term plan exists.

There are religious parallels to this secular tradition. For example, during Judaism's New Year, Rosh Hashanah, through the High Holidays and culminating in the Day of Atonement, or Yom Kippur, one is to reflect upon one's wrongdoings over the year and both seek and offer forgiveness. The concept, regardless of creed, is to reflect upon self-improvement annually.

Recent research shows that while 52% of participants in a resolution study were confident of success with their goals, only 12% actually achieved their goals. Men achieved their goal 22% more often when they engaged in goal setting, a system where small measurable goals are used (lose a pound a week, instead of saying "lose weight"), while women succeeded 10% more when they made their goals public and got support from their friends and achieving their goals are very important.