This presentation on By-products was held for a training program out of Dhaka, at Natore district, involving 60 participants. A by-product is defined as the secondary product derived from a manufacturing process or chemical reaction. It is not the primary product or service being produced. In the context of production, a by-product is the 'output from a joint production process that is minor in quantity and/or net realizable value (NRV) when compared to the main products.

As calls for bolstering environmental services on croplands have grown more insistent during the past two decades, the search for ways to foster sustainable, reduced input agriculture has become more urgent. In this context authors re-examine by means of a meta-analysis the argument, first proposed by Robert McC. Netting, that small scale, mixed crop – livestock farming, a common livelihood among poor rural peoples, encourages environmentally sustainable agricultural practices.