In 2007, Professor Hans J. Schlitt created associating liver partition and portal vein ligation for staged hepatectomy. In 2012, Professors de Santibañes E and Pierre-Alain Clavien officially named the procedure ALPPS [1–3]. Since then, it has received widespread attention and rapidly popularized in practices [4–14]. It enables fast induction of future liver remnant (FLR) hypertrophy and a very high resection rate, giving many patients who were initially unresectable the opportunity of radical tumor resection. The principle of ALPPS is to separate the tumor-bearing part of the liver and the FLR by ligating or embolizing portal vein branches in the former and partitioning liver parenchyma, inducing FLR hypertrophy. The second stage of surgery (tumor resection) may proceed when adequate FLR growth is achieved. In the early years, classical ALPPS meant right trisectionectomy ALPPS or extended right hemihepatectomy ALPPS. In the first stage, parenchymal separation and ligation of the right portal vein are performed; Glisson branches of segment IV are completely or partially divided simultaneously; the tumor is removed in the second stage [15, 16]. Classical ALPPS induced FLR hypertrophy effectively, with a high resection rate. Nonetheless, it is relatively invasive, producing high complication and mortality rates. At the dawn of its development, the incidences of perioperative complication and 90-day mortality were as high as 68% and 12%, respectively. Its safety attracted concerns and evoked great controversy [3]. Since then, to reduce the complication and mortality rates and improve its safety, many scholars have made various improvements and derived a variety of ALPPS modifications, including Partial ALPPS, where only part of the liver parenchyma is separated in the first stage, Radiofrequency-assisted ALPPS (RALPPS), associating microwave ablation and portal vein ligation for staged hepatectomy (AMAPS) and tourniquet ALPPS (sometimes called ALTPS: associating liver tourniquet and portal ligation for staged hepatectomy where the liver partition is replaced by radiofrequency/microwave ablation or tourniquet separation, and operations performed using minimally invasive techniques (laparoscopy and robotics) [4, 16–36]. With accumulated cases, it is demonstrated that partial liver partition and separation by RFA, MWA, or tourniquet in the first stage can achieve an FLR induction similar to the classical ALPPS for patients without severe chronic liver diseases. The definition of ALPPS has also transitioned from classical liver partition to liver separation with more flexible applications, namely, the number of tumors, site of FLR, and the number of residual liver segments are no longer limited. Reversal ALPPS, mesohepatectomy ALPPS, and monosegment ALPPS drive the advancement, re-interpreting ALPPS’s surgical principles while exemplifying its core components. The required site of FLR is no longer limited to the left lateral lobe or the left liver, any lobe, any segment, or even any area with independent and complete vascular structure and function, can be singled out as the FLR for hypertrophy induction [21, 37, 38]. Its indications are thus expanded prominently. These modified procedures also validate the rationale and the two core elements of ALPPS from one side of the spectrum: separation of the tumor side and FLR as well as portal vein occlusion of the tumor-side. Thanks to the unremitting exploration and joint efforts of hepatobiliary surgeons worldwide, and their continuous innovation, summary, and improvement of ALPPS, the current understanding of its surgical principles is well-established, with new procedures and flexible approaches emerging. According to the 10-year analysis by the ALPPS International Registry, the number of modified ALPPS has increased, accounting for half of all ALPPS cases [15].