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In recent years industry has seen a paradigm shift with the advent of Full Waveform Inversion (FWI) imaging in 3D seismic data processing projects. Fundamentally this is a directional derivative of a velocity model, the resolution of which is controlled by the maximum frequency of the FWI and of course the subsurface properties. FWI was first proposed by Tarantola (1984), due to the lack of cost-effective computers the uptake was limited. Sirgue et al (2010) published an example that accelerated development when FWI was run to 7Hz, to provide a significant uplift in imaging underneath a gas cloud. For many years FWI was run to 7Hz or 10Hz. Shen et al (2018) demonstrated the importance to subsalt imaging by extending beyond these traditional FWI frequencies, whilst Wei et al (2023) published a series of examples to demonstrate the value in 3D of extending FWI to frequencies in excess of 100Hz. FWI has several potential advantages over conventional imaging, it is an iterative least squares solution of the full wavefield and thus has the ability to provide cleaner attributes as a result of the least squares nature of the process. As FWI uses the full wavefield (primary and multiples) it is possible to generate an image over a larger area relative to area obtained from single iteration, primary only RTM. FWI imaging has also enabled turnaround time for projects to be significantly reduced. Despite the progress made, there are still very few published examples of using FWI imaging in 4D. In this paper we show the application of 4D FWI technology to show a towed streamer example offshore Nigeria. We will share examples of parallel 4D FWI (run FWI on each 3D and subtracting) versus a joint 4D FWI scheme, which produces equivalent results, but requires only around half the number of total iterations per frequency band relative to the parallel approach and has the advantage of using the 4D signal within the update. We then compare the results of the 4D FWI with a conventional 4D processing workflow, discuss the advantages and disadvantages of each and highlight future considerations.