The　proliferation　of　novel　wastewater　treatment　processes　has　marked　recent　years,　becoming　particularly　pertinent　in　light　of　the　strive　for　carbon　neutrality.　One　area　of　growing　attention　within　this　context　is　nitrous　oxide　(N2O)　production　and　emission.　This　review　provides　a　comprehensive　overview　of　recent　research　progress　on　N2O　emissions　associated　with　novel　wastewater　treatment　processes,　including　Anammox,　Partial　Nitrification,　Partial　Denitrification,　Comammox,　Denitrifying　Phosphorus　Removal,　Sulfur-driven　Autotrophic　Denitrification　and　n-DAMO.　The　advantages　and　challenges　of　these　processes　are　thoroughly　examined,　and　various　mitigation　strategies　are　proposed.　An　interesting　angle　that　delve　into　is　the　potential　of　endogenous　denitrification　to　act　as　an　N2O　sink.　Furthermore,　the　review　discusses　the　potential　applications　and　rationale　for　novel　Anammox-based　processes　to　reduce　N2O　emissions.　The　aim　is　to　inform　future　technology　research　in　this　area.　Overall,　this　review　aims　to　shed　light　on　these　emerging　technologies　while　encouraging　further　research　and　development.　©　2023　Elsevier　Ltd