It is becoming abundant in Addis Ababa, to conservatively place high-rise buildings onrndeeper hard stratum through very long piles. However, the use of piled raft foundationrnseems to be more advantageous than the conventional pile foundation since both the raftrnand piles contribute to the resisting capacity of the system. In an attempt to investigate thernextent of this principle, a case study was undertaken in this paper. The case underrnconsideration, ORDA project of Addis Ababa, incorporates three blocks of differentrnheight, accessed as one building. The highest block of the structure rested on long piles torntransfer the load to a basalt layer found at a great depth. In the study, the as-builtrnconventional pile foundation scheme was analyzed and compared with that of a proposedrnpiled raft foundation system. In doing so, a finite element analysis software, ABAQUS,rnwas utilized to investigate the behavior of the foundation systems under study. The Effectrnof one block on the other as well as differential settlement due to varying loads of thernblocks is considered in the analysis. rnThe analysis result revealed that the proposed piled raft foundation was able to safelyrnsupport the vertical load coming from the super structure by utilizing a shorter and muchrnsmaller number of piles than used in the as-built foundation system. It was possible tornreduce the number of piles from 162 to 50 and the length of piles from 25.4m to 20.4m,rnwith the adequate margin of safety. The enormous economic benefit of using piled rafts isrnalso shown through direct comparison of expenses for the as-built and proposedrnfoundations. A potential cost reduction of 75% was observed in the analysis.