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Vitamin B6 is derived primarily from plant sources and is an essential nutrient in the human diet. While it is well established as a cofactor for numerous metabolic enzymes, more recently, vitamin B6 has been implicated as a potent antioxidant. The term vitamin B6 is generic for the compounds pyridoxine (PN), pyridoxal, pyridoxamine and their phosphorylated derivatives (vitamers). The de novo biosynthesis pathway of the vitamin in plants has recently been unravelled and involves only two proteins, PDX1 and PDX2, that directly synthesize the cofactor vitamer, pyridoxal 5′-phosphate. There is also a salvage pathway that can interconvert the six vitamers. The isolation of mutants in either the salvage or de novo biosynthesis pathway has provided enormous insight into the role of this vital set of compounds in metabolic, physiological and developmental processes in plants. Due to both its cofactor and antioxidant role, the vitamin has been implicated in both abiotic and biotic stress responses in plants. The dual role of the vitamin is beginning to provide insight into the homeostatic maintenance of this set of compounds with exciting new areas of research being uncovered. Here an impression of the vital roles this vitamin plays as well as the general properties of the vitamin in plants is provided.