This paper reported a first semi-controlled study on the impact of aspect-oriented designs (AOD) on software changeability. The study produced intriguing outcomes on AOD evolvability, in comparison with OO designs, such as ripple effects manifesting through aspect interfaces while changing non-aspectual modules. Quoting a reviewer: ""this paper provides an interesting, in-depth, and valuable study of the software engineering implications of AO versus OO, quite possibly the best of its kind (certainly the best I have seen)."" The ECOOP conference series has an outstanding impact factor of 1.95 (Citeseer, 2003), higher than OOPSLA (1.89) and ICSE (0.90). Acceptance rate in 2007 = 15%. RAE_import_type : Conference contribution RAE_uoa_type : Computer Science and Informatics