The paper estimates global average sea level rise from 1993 to 2009 using satellite altimeter data and from 1880 to 2009 using coastal and island sea-level measurements. The satellite data show an estimated rate of rise of 3.2 ± 0.4 mm year⁻¹, while the in situ data yield a rate of 2.8 ± 0.8 mm year⁻¹. The global average sea-level rise from 1880 to 2009 is about 210 mm. The linear trend from 1900 to 2009 is 1.7 ± 0.2 mm year⁻¹, and since 1961 it is 1.9 ± 0.4 mm year⁻¹. There has been a statistically significant acceleration in sea-level rise since 1880 and 1900, at rates of 0.009 ± 0.003 mm year⁻² and 0.009 ± 0.004 mm year⁻², respectively. Since the start of the altimeter record in 1993, the rate of sea-level rise has been near the upper end of projections by the Intergovernmental Panel on Climate Change. However, there was little net change in sea level from 1990 to 1993, likely due to the volcanic eruption of Mount Pinatubo in 1991. The study highlights the importance of maintaining and expanding the observing network and improving the accuracy of satellite altimeter measurements.The paper estimates global average sea level rise from 1993 to 2009 using satellite altimeter data and from 1880 to 2009 using coastal and island sea-level measurements. The satellite data show an estimated rate of rise of 3.2 ± 0.4 mm year⁻¹, while the in situ data yield a rate of 2.8 ± 0.8 mm year⁻¹. The global average sea-level rise from 1880 to 2009 is about 210 mm. The linear trend from 1900 to 2009 is 1.7 ± 0.2 mm year⁻¹, and since 1961 it is 1.9 ± 0.4 mm year⁻¹. There has been a statistically significant acceleration in sea-level rise since 1880 and 1900, at rates of 0.009 ± 0.003 mm year⁻² and 0.009 ± 0.004 mm year⁻², respectively. Since the start of the altimeter record in 1993, the rate of sea-level rise has been near the upper end of projections by the Intergovernmental Panel on Climate Change. However, there was little net change in sea level from 1990 to 1993, likely due to the volcanic eruption of Mount Pinatubo in 1991. The study highlights the importance of maintaining and expanding the observing network and improving the accuracy of satellite altimeter measurements.