The role and contribution of the fisheries sub-sector in Kenya cannot be underestimated. In particular, the contribution of Rastrienebola Argentea, commonly referred to as Omena, or Dagaa is increasingly being recognized and appreciated by several Government institutions and Non-Governmental organizations. Omena production is valued at 200 million dollars while its trade supports more than 2 million livelihoods. Different interventions by the government and the Non-Governmental organizations have resulted to increased production of Omena fish. However, increased production alone is not enough to effectively develop this industry. Information on the marketing functions and the efficiency with which these functions are carried out is lacking. In addition, distribution of costs and benefits along the Omena marketing chain is not known while fluctuations in supply affect price transmission between different markets. The main objective of this study was thus to assess the performance of Omena marketing in Kenya. The specific objectives of the study included: assessing the effectiveness of the Omena marketing channels; evaluating the price spreads along the different marketing channels; and to determine whether the spatially separated markets for Omena are integrated. Primary data was collected in two purposively identified regional markets in Kenya (i.e. Kisumu and Nakuru) while additional secondary data from the Nairobi region was included only for the purposes of analyzing market integration. Selection of markets was based on whether the markets are deficit or surplus regions for Omena. A multistage sampling procedure resulted to a total of 43 fishermen; 42 small scale processors; 20 wholesalers; 31 retailers; 32 domestic consumers; and 7 industrial consumers making a grand total number of 175 respondents. Questionnaires were adopted as the major tools of data collection using one-on-one interviews. To analyze the resultant data, the study utilized gross margin analysis and co-integration modeling. Results indicate that Omena marketing channels are to a large degree effective as it regards to meeting the consumption needs. However, results also indicated that longer marketing channels resulted not only to high costs and thus high retail prices; but also to lower returns to the fishermen. Further, the study identified that there is no integration amongst Omena markets in Kisumu and Nakuru and that a weak degree of integration existed between Kisumu and Nairobi. Information generated by this study is important in guiding policy makers to identify points of interventions as well as in designing effective and efficient Omena marketing channels.