During a development project, one or more design professionals will be typically engaged by the developer early in the process. Those design professionals may assist in creating a topographical map, an exterior architectural design for the project, developing a drainage plan or a plan for the contouring of the land suitable for the project through a series of cuts and fills, or a landscaping plan. In an era when development costs have skyrocketed, while development money is scarce and investors leery, the financial risks of the development process make it imperative that the design professional be cautious about allowing the development client to incur too large of an account receivable. And it behooves the design professional to become familiar with the design professional lien. Which Design Professionals Have Lien Rights? For over twenty years, California law has defined a “design professional” as an architect, an engineer, or a land surveyor.