Systems, methods, devices, and other techniques for placing and rendering virtual objects in three-dimensional environments. The techniques include providing, by a device, a view of an environment of a first user. A first computing system associated with the first user receives an instruction to display, within the view of the environment of the first user, a virtual marker at a specified position of the environment of the first user, the specified position derived from a second user's interaction with a three-dimensional (3D) model of at least a portion of the environment of the first user. The device displays, within the view of the environment of the first user, the virtual marker at the specified position of the environment of the first user.