Systems and methods of support structures in powder-bed fusion (PBF) are provided. Support structures can be formed of bound powder, which can be, for example, compacted powder, compacted and sintered powder, powder with a binding agent applied, etc. Support structures can be formed of non-powder support material, such as a foam. Support structures can be formed to include resonant structures that can be removed by applying a resonance frequency. Support structures can be formed to include structures configured to melt when electrical current is applied for easy removal.