C HAP TE R 6 Cost allocation joint-cost situations Teaching tips and points to stress Meaning of joint products and byproducts terms The discussion in Chapter 6 of joint costs and byproducts is a special case of allocating common costs to products. The joint costs are caused by the decision to produce the market basket of products. Joint-costing problems are particularly troublesome because it is not feasible to apply the cause-and-effect criterion. If a product yields only one product with a relatively high sales value, that product is termed a main product. The term joint product is reserved for cases where the production process yields multiple high sales value products.