Partial　nitrification　has　gained　broad　interests　in　the　biological　nitrogen　removal　(BNR)　from　wastewater,　since　it　alleviates　carbon　limitation　issues　and　acts　as　a　shortcut　nitrogen　removal　system　combined　with　anaerobic　ammonium　oxidation　(Anammox)　process.　The　occurrence　and　maintenance　of　partial　nitrification　relies　on　various　conditions,　which　favor　ammonium　oxidizing　bacteria　(AOB)　but　inhibit　or　limit　nitrite　oxidizing　bacteria　(NOB).　The　studies　of　the　AOB　and　NOB　activities　have　been　conducted　by　state-of-the-art　molecular　techniques,　such　as　Polymerase　Chain　Reaction　(PCR),　Quantitative　PCR,　denaturing　gradient　gel　electrophoresis　(DGGE),　Fluorescence　in　situ　hybridization　(FISH)　technique,　Terminal　Restriction　Fragment　Length　Polymorphism　(T-RFLP),　Live/Dead　BacLight,　and　quinone　profile.　Furthermore,　control　strategies　for　obtaining　partial　nitrification　are　mainly　focused　on　the　pH,　temperature,　dissolved　oxygen　concentration,　real-time　aeration　control,　sludge　retention　time,　substrate　concentration,　alternating　anoxic　and　aerobic　operation,　inhibitor　and　ultrasonic　treatment.　Existing　problems　and　further　perspectives　for　the　scale-up　of　partial　nitrification　are　also　proposed　and　suggested.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.