The mandate of the department is to transform Kenya 's arid and semi-arid into vibrant economic development areas by reclaim and sustainably exploiting Kenya 's arid and semi-arid lands (ASALs) potential for economic development .
The ASALs covers about 467,200Km2 which is 80% of the country's landmass of 584,000Km2. The ASAL have been increasing due to land degradation and settlements due to migration from the high potential areas. The ASALs cover 44 districts; 28 of which are about 30% ASAL; while 7 are between 30% and 85% ASAL; and 9 of them are more than 85% ASAL.