SPECT myocardial perfusion imaging is a clinical standard for the care of cardiac patients. During the past 2 decades, this method has continued to evolve and significant improvements in image quality have been realized. Despite these continued improvements, imaging artifacts remain problematic and often confound accurate image interpretation. The most frequent and difficult cause of myocardial perfusion imaging artifacts continues to be related to soft tissue attenuation and resultant photon attenuation. Methods for non-uniform attenuation correction have progressed slowly until recently, but there are now a number of techniques, which offer true correction for photon attenuation. Clinical validation has demonstrated clear clinical benefits for this technology and the field of nuclear cardiology enthusiastically supports these technical advances. However, additional clinical validation is warranted especially for commercially available systems that have not yet been evaluated with rigor.