The authors have developed techniques to measure the 230Th abundance in corals using isotope dilution mass spectrometry, which, combined with their previous development of mass spectrometric techniques for 234U and 232Th measurement, has significantly reduced analytical errors in 238U-234U-230Th dating and sample size. They demonstrate that 6 × 10^8 atoms of 230Th can be measured to ±30% (2σ) and 2 × 10^10 atoms to ±2%e. The time range for useful age data on corals is from a few years to ~500,000 years. The uncertainty in age, based on analytical errors, is ±5 years for a 180-year-old coral (3 g), ±44 years at 8294 years, and ±1.1ky at 123.1ky (250 mg of coral). They also report 232Th concentrations in corals that are more than two orders of magnitude lower than previous values. Ages with high analytical precision were determined for several corals that grew during high sea level stands ~120,000 years ago, supporting the idea that the dominant cause of Pleistocene climate change is Milankovitch forcing.The authors have developed techniques to measure the 230Th abundance in corals using isotope dilution mass spectrometry, which, combined with their previous development of mass spectrometric techniques for 234U and 232Th measurement, has significantly reduced analytical errors in 238U-234U-230Th dating and sample size. They demonstrate that 6 × 10^8 atoms of 230Th can be measured to ±30% (2σ) and 2 × 10^10 atoms to ±2%e. The time range for useful age data on corals is from a few years to ~500,000 years. The uncertainty in age, based on analytical errors, is ±5 years for a 180-year-old coral (3 g), ±44 years at 8294 years, and ±1.1ky at 123.1ky (250 mg of coral). They also report 232Th concentrations in corals that are more than two orders of magnitude lower than previous values. Ages with high analytical precision were determined for several corals that grew during high sea level stands ~120,000 years ago, supporting the idea that the dominant cause of Pleistocene climate change is Milankovitch forcing.