Zonal isolation is reliant on successful cement placement. Part of the key criteria to achieve zonal isolation includes effective mud removal and fluid displacement efficiencies. To meet the mud removal requirements, a spacer system promoting physical or mechanical scrubbing appears to increase the efficiency of filter cake removal. The spacer has been deployed in Saudi Arabian wells containing water- and oil-based mud systems. For any given application, this paper discusses advanced laboratory testing to obtain performance properties such spacer stability and spacer integrity while managing the downhole plugging risks. This paper will document examples demonstrating results the spacer performance including cement evaluation logs supporting the use for achieving similar cement placement objectives.