The cytokines lymphotoxin (LT) α, β and their receptor (LTβR) belong to the tumor necrosis factor (TNF) superfamily, whose founder—TNFα—was initially discovered due to its tumor necrotizing activity. LTβR signaling serves pleiotropic functions including the control of lymphoid organ development, support of efficient immune responses against pathogens due to maintenance of intact lymphoid structures, induction of tertiary lymphoid organs, liver regeneration or control of lipid homeostasis. Signaling through LTβR comprises the noncanonical/canonical nuclear factor-κB (NF-κB) pathways thus inducing chemokine, cytokine or adhesion molecule expression, cell proliferation and cell survival. Blocking LTβR signaling or Fcγ-receptor mediated immunoablation of LT-expressing cells was demonstrated to be beneficial in various infectious or noninfectious inflammatory or autoimmune disorders. Only recently, LTβR signaling was shown to initiate inflammation-induced carcinogenesis, to influence primary tumorigenesis and to control reemergence of carcinoma in various cancer models through distinct mechanisms. Indeed, LTβR signaling inhibition has already been used as efficient anti-inflammatory, anti-cancer therapy in some experimental models. Here, we review the pleiotropic functions attributed to LT, the effects of its deregulation and extensively discuss the recent literature on LT's link to carcinogenesis.