Objectives: Purposeful SDM posits four modes of shared decision making (SDM). The use of each mode depends on the type of problem of care that is being addressed. We sought to identify how current observer-based SDM measures apply to each mode of Purposeful SDM. Methods: Four coders, working independently, evaluated 192 items pertaining to 12 observer-based SDM process measures. They classified the items into 6 themes that vary across Purposeful SDM modes and then into one of the four modes (weighing, negotiating, problem-solving, developing insight). Disagreements were resolved by consensus. Results: The items were classified as pertaining to the following themes: problem (28), roles/participation (84), options (62), preferences (21), decision (15), and evaluation (6). They were then classified as pertaining particularly to the SDM modes of weighing (54), negotiating (5), problem-solving (0), and developing insight (0) modes, with 191 items applying broadly to all modes of Purposeful SDM. Conclusions: Observer-based SDM measures describe behaviors pertinent to all modes but lack items sensitive to behaviors particular to some modes of SDM. Practice Implications: New or revised observer-based measures of the SDM process could help estimate the extent to which the appropriate SDM mode is being used to address the patient's problem.