There is little information on the status and trends of the Black-legged Kittiwake (Rissa tridactyla) colonies in Greenland. This study analyses and evaluates historical counts from 1920-1999 of kittiwake colonies that have had ≥1,000 breeding pairs and have been counted at least twice. Fifty colonies fulfilled these criteria. Thirty-four of these colonies declined by between 50-100%. Data suggest that the decline has occurred throughout most of the country. Only five colonies had increased and eleven had remained stable or fluctuated with no clear trend. The increasing colonies do not compensate for the overall decline. Despite the heterogeneity of the count years and varying degree of count quality, the data suggest a dramatic decline within the last century. Data analysis does not suggest that local hunting, egg collecting or disturbance at the breeding colonies have been major causes for the decline and other causes should be considered. Causes of the decline remain unknown.