The present invention relates to positioning guidance for image acquisition. In order to facilitate positioning of a patient for medical image acquisition a guiding system (14) is provided. The system comprises a patient detecting device (22) and a patient position prescribing device (24). The patient detecting device is configured to detect an anatomy of interest (36) of a patient for image acquisition and to detect current spatial information of the anatomy of interest. The patient position prescribing device is configured to provide an initial target position (40) for the detected anatomy of interest wherein the initial target position is provided as a reference for the image acquisition. The patient position prescribing device is further configured to register the initial target position with the current spatial information and to determine an adapted target position (42) by adapting the initial target position based inter alia on the current spatial information.