The 1991 Social Accounting Matrix (SAM) for Zimbabwe that we document in this paper is intended to provide benchmark data for economy-wide analysis under the MERRISA Project. Its construction is based on a three-step process: (1) building a macro SAM that presents the aggregative features of the Zimbabwean economy and serves as a control matrix for the micro SAM; (2) disaggregation into a complete but unbalanced micro SAM; and (3) balancing the disaggregated and complete micro SAM using the cross-entropy approach. The macro SAM entries are based on aggregates from a recent, significant revision of the Zimbabwe national accounts for 1991. The structure of the micro SAM is a disaggregated version of the macro SAM. The outcome is an 88 by 88 matrix that includes 36 activities, 27 commodities, 9 factors of production (4 labor, 3 capital, and 2 land categories), 5 households groups, and one account each for enterprises, government, investment/saving, and rest-of-the-world. Among the significant features of the Zimbabwean economy that are explicitly taken into account in the SAM structure are the importance of agriculture, the distinction between smallholder and large-scale commercial farms, home consumption by smallholder farm households, and the large marketing margins that reflect inefficiencies in trade and transport infrastructure.