Fundamental phase in the preliminary design of an aircraft is the load case choice. Historically, the manoeuvres have been considered as the principal critical loads, while in conceptual design the gusts have been not investigated since, being an intrinsically dynamic phenomenon, they are expensive to analyze. Nevertheless, they are a critical certification requirement which is becoming more and more demanding with the introduction of composite materials and high aspect-ratio wings. There is, however, an absence of methodical ways to take decisions regarding including the gust loads into the optimization in conceptual design. This MSc thesis aims to define design guidelines for gust loads inclusion in aeroelastic optimization for the civil transport aircraft category. Several optimization cases are computed in the TU Delft in-house aeroelastic framework PROTEUS, varying main design parameters, materials and gust models to understand the sensitivity of the design to the gust response analysis.