## 1 Introduction
By employing data collected from this survey, we present the distribution of green purchasing rates of Japanese municipalities by category and derive implications for green public purchasing and green consumption. Moreover, we examine the relationship between the green purchasing rates of municipalities and their green purchasing policy (GPP). GPP is an action plan and/or a policy commitment that helps governments implement green purchasing. Therefore, establishing GPP is very likely to make the strategic goals of an organization clearer and as a result, make its staff awareness higher and make it easier to gain senior management support. We analyze the relationship between purchasing and policy because policy or action plans for green purchasing are recognized as powerful drivers of green purchasing implementation [26]. Operating with the same understanding, the sustainable purchasing research initiative (SPRI) has conducted surveys of local governments in several countries to identify the status of their GPP and to make policy recommendations [27; 28; 29]. To examine whether the presence or absence of a GPP is related to green purchasing performance (and the measurement of that performance), we conduct regression analyses. We verify the hypothesis that a GPP helps governments implement green purchasing. We focus on local municipalities for the following two reasons. The first reason is that local municipalities have not been doing as well in green purchasing as the national authorities and prefectures. However, municipalities have accounted for a large percentage of the total public spending although they are small. Thus, we cannot ignore the role of municipalities in making public procurement even greener and thus, we focus on them. The second reason is that there is a variation in the adaptation of GPPs among local municipalities. This variation is necessary for examining the relationship between green purchasing rates and GPP. As all of the prefectural governments and designated cites have implemented green purchasing and adopted related policies, we cannot compare entities that have adopted GPPs with those that have not at this administrative level. Thus, the contributions of this paper are twofold: first, by using data with comprehensive item categories relative to previous studies, it identifies the categories that are easier or harder for local municipalities to implement green purchasing in. If we can understand these aspects of green purchasing, we can identify which categories we should focus on as policy targets. This understanding will help us form a policy to promote green purchasing in an efficient way, especially for small and medium organizations. Second, we identify the relationship between green purchasing performance and policy and determine whether and how the relationship is different between item categories. Identifying the role and the extent of GPP in promoting green purchasing will be useful for local municipalities across the globe (not only for Japan but also for the rest of the world). The next section will explain the background of Japan's green purchasing and the survey analyzed in this paper. The third section will present the results of data analysis. The fourth section will discuss the regression results. The final section will discuss the implications of the results and conclude this paper.