Megavoltage planning—level 4 Stereotactic body radiation therapy (SBRT) simulation and dosimetry for treatment planning, if: (a) all of the following apply in relation to the simulation: (i) treatment set‑up and technique specifications are in preparation for inverse planning with multiple non‑coplanar, rotational or fixed beam stereotactic delivery or intensity modulated radiation therapy (IMRT) stereotactic delivery; (ii) personalised patient set‑up and immobilisation techniques are suitable for reliable imaging acquisition and reproducible, including techniques to minimise motion of organs at risk and targets; (iii) small‑field and ablative treatment is used; (iv) a high‑quality three‑dimensional or four‑dimensional image volume dataset is acquired in treatment position for the relevant region of interest to be planned, treated and verified (through daily planar or volumetric image guidance strategies); and (b) all of the following apply in relation to the dosimetry: (i) the planning process is required to calculate dose to single or multiple target structures and requires a dose‑volume histogram to complete the planning process; (ii) based on review and assessment by a radiation oncologist, the planning process maximises the differential between target dose, organs at risk and normal tissue dose; (iii) all relevant gross tumour volumes, clinical target volumes, planning target volumes and organs at risk are rendered and nominated with planning dose objectives; (iv) organs at risk are nominated as planning dose constraints; (v) dose calculations and dose‑volume histograms are generated using a validated stereotactic‑type algorithm, with prescription and plan details approved and recorded with the plan Applicable once per course of treatment