Wastewater　treatment　plants　(WWTPs)　are　facing　a　great　challenge　to　transition　from　energy-intensive　to　carbon-neutral　and　energy-efficient　systems.　Biological　nutrient　removal　(BNR)　can　be　severely　impacted　by　carbon　limitation,　particularly　for　wastewater　with　a　low　carbon-to-nitrogen　(C/N)　ratio,　which　can　significantly　increase　the　operational　costs.　Waste　activated　sludge　(WAS)　is　a　valuable　byproduct　of　WWTPs,　as　it　contains　high　levels　of　organic　matter　that　can　be　utilized　to　improve　BNR　management　by　recovering　and　reusing　the　fermentative　volatile　fatty　acids　(VFAs).　This　review　provides　a　comprehensive　examination　of　the　recovery　and　reuse　of　VFAs　in　wastewater　management,　with　a　particular　focus　on　advancing　the　preferable　biological　short-cut　nitrogen　removal　process　for　carbon-insufficient　municipal　wastewaters.　First,　the　method　of　carbon　redirection　for　recovering　VFAs　was　reviewed.　Carbon　could　be　captured　through　the　two-stage　A/B　process　or　via　sludge　fermentation　with　different　sludge　pretreatment　and　process　control　strategies　to　accelerate　sludge　hydrolysis　and　inhibit　methanogens　to　enhance　VFA　production.　Second,　VFAs　can　support　the　metabolism　of　autotrophic　N-cycling　microorganisms　involved　in　wastewater　treatment,　such　as　AOB,　NOB,　anammox,　and　comammox　bacteria.　However,　VFAs　can　also　cause　inhibition　at　high　concentrations,　leading　to　the　partition　of　AOB　and　NOB;　and　can　promote　partial　denitrification　as　an　efficient　carbon　source　for　heterotrophic　denitrifiers.　Third,　the　lab-　and　pilot-scale　engineering　practices　with　different　configurations　(i.e.,　A2O,　SBR,　UASB)　were　summarized　that　have　shown　the　feasibility　of　utilizing　the　fermentate　to　achieve　superior　nitrogen　removal　performance　without　the　need　for　external　carbon　addition.　Lastly,　the　future　perspectives　on　leveraging　the　relationships　between　mainstream　and　sidestream,　nitrogen　and　phosphorus,　autotrophs　and　heterotrophs　were　given　for　sustainable　and　efficient　BNR　management.　©　2023