ISO 9001 (2000 and 2008), Quality management systems – Requirements are globally the most used standard. The total number of issued certificates tends to increase year by year, according to the annual surveys of International Organization for Standardization (ISO). The situation In Latvia is similar – the total number of the standard user organizations grows every year only in much smaller amount. However, the information about issued certificates is insufficient for realizing an in-depth analysis of standard user organizations. This study is valuable for providing detailed information about enterprises by size classes and for information about proportion of certified enterprises to overall number of enterprises to observe the most active scale group of business for ISO 9001 certification. The expected research outcome – the number of certified enterprises and their distribution by size class (micro, small, medium-sized and large scale enterprises) in Latvia.