In this paper the Organization for Economic Cooperation Development (OECD) approach (adjusted) is applied to estimate the size of the non-observed economy (NOE) in Bosnia and Herzegovina for the year 2001. The method proposed attempts to identify the structure of the NOE according to the reasons behind the unrecorded value added (statistical, illegal and economic). The NOE was estimated for each of the Bosnian entities separately according to sector of activity. A definition of the shadow economy is proposed based on SNA93. A comparison with alternative estimates of shadow economies in Central and Eastern European countries is provided.