"All I Have" is a song by American singer Jennifer Lopez, featuring American rapper LL Cool J. Written by Lopez, Makeba Riddick, Curtis Richardson, and Ron G and produced by Cory Rooney, Ron G, and Dave McPherson, it was released in early 2003 as the second single from Lopez's third studio album, This Is Me... Then(2002). The song reached number one in the United States and New Zealand, and entered the top five and the top ten in several countries. After the success of "All I Have" with LL Cool J, the track was later included on the re-issue of his album 10.

The song is based around a sample from Debra Laws' 1981 song "Very Special", written by Lisa Peters and William Jeffrey. It was originally intended to be titled "I'm Good", but was changed because it sounded too similar to her 2001 hit "I'm Real".

The music video for the single was shot in New York City in November 2002 and released in January 2003. It features Lopez and LL as former lovers now broken up. The two recall the good and bad times while dealing with being alone for the holidays. Lopez shows up to LL's house with a gift. With him not there, she puts the gift under the tree. He later sees the gift under the tree and realizes it was from Lopez. He opens the gift and sees a golden key. Upset at the relationship being over, he throws the key in the fireplace while a tearful Lopez gets help from her friends with her things. The video was shot right before Thanksgiving, but did not premiere on television until after Christmas.

On the U.S. Hot 100, "All I Have" debuted at number twenty-five the last charting week of 2002, which was December 28, easily becoming the highest-debuting song of that year. "All I Have" made impressive strides on the survey, reaching the penthouse by February 8, 2003, where it remained for four weeks, becoming Lopez's fourth Hot 100 number-one single and the first for LL. The single was one of the most popular pop and R&B singles of the spring of 2003, remaining in the top ten for twelve weeks, nineteen weeks on the top thirty, and twenty-one weeks on the top fifty. Moreover, it charted inside the top five in the United Kingdom, the Netherlands, Switzerland, and Australia and the top ten in Canada and Ireland.

In March 2003, Debra Laws sued Sony Music Entertainment/Epic Records in the United States District Court for the Central District of California, claiming that the use of samples from "Very Special" without her consent (even though the writers of "Very Special" and Elektra Entertainment Group—successor to Elektra/Asylum Records, which had released the original recording of "Very Special"—had given their consent to the use of the samples) violated her statutory and common law right of publicity under California law. In November 2003, Judge Lourdes Baird granted Sony Music's motion for summary judgment on the ground that Laws's state law claims were preempted by Section 301 of the United States Copyright Act. In 2006, that decision was affirmed by the United States Court of Appeals for the Ninth Circuit.