As systems become more complex, it is increasingly important that people in functional roles such as systems engineers and logisticians have effective means, either formal ones such as IPTs or informal ones such as social networks, whereby each role can understand the effects that decisions in other functions have on their function and vice-versa. Moreover, it is equally important that people in functional roles learn how to use such means to transmit
knowledge across functions, as well as influence decisions in other functions in making needed trade-offs. This requires both technical knowledge (e.g., the technical aspects of interactions between functions) and professional knowledge (e.g., how to elicit issues of concern and to influence decisions). For example, designing a system to be modular may result in reduced sustainment cost, as repairs and upgrades to deployed systems tend to be less costly,
but it may also result in increased costs for design and development [1]. The systems engineer and logistician, in this case, must understand the technical aspects of the interaction between modularity and cost and use influence or negotiation to make the right trade-off.