This paper explores issues that designers of learning environments should consider, omitting issues about knowledge learned and the social settings in which learning occurs that are addressed elsewhere. The perspective taken on design is to think of each decision in terms of its costs and benefits, an approach that may allow designers to minimize costs and maximize benefits of design decisions. The first issue to address in the design of any learning environment is authenticity, and the goal of authenticity is to prepare students to do the kinds of complex tasks that occur in life. The cost-benefit trade-offs that are dealt with in this paper are organized under four topics: (1) goals; (2) learning style; (3) sequence; and (4) methods. Learning goals that should be considered are those of memorization versus thoughtfulness, whole tasks versus component skills tasks, breadth versus depth of knowledge, diverse versus uniform expertise, access versus understanding, and cognitive versus physical fidelity. Learning style issues include interactive versus active versus passive learning, incidental versus direct learning, natural versus efficient learning, and whether or not the learner is in control. Because a learning environment changes as a person interacts with it, some of the design tradeoffs must be considered sequentially; hence, it is proposed that the trade-offs between grounded versus abstract learning, structured versus exploratory learning, systematic versus diverse learning, and simple versus complex learning be treated this way. And, finally, in regard to methods, the following teaching methods that are associated with cognitive apprenticeship and the design of learning environments may be considered by the designer: (1) modeling; (2) scaffolding; (3) coaching; (4) articulation; and (5) reflection. (Contains 32 references.) (SLD)