New Zealand has fossil remains of one of the largest known extinct penguin; a "giant" at 1.5m, yet currently the penguins that inhabit New Zealand include one of the smaller species at 0.38m. This seeming paradox will be discussed in this review, looking at gigantism in fossil and living penguins. The distribution of living penguins is related to their size, physiology, evolution and special adaptations to the cold. The fossil distribution is harder to analyse because of the incomplete nature of information gleaned from fossils. The issues canvassed include evolution, geological and climate changes. The conclusion is that the distribution of fossil and living giant penguins require different explanations. Summary New Zealand has fossil remains of one of the largest known extinct penguin; a "giant" at 1.5m, yet currently the penguins that inhabit New Zealand include one of the smaller species at 0.38m. This seeming paradox will be discussed in this review, looking at gigantism in fossil and living penguins. The distribution of living penguins is related to their size, physiology, evolution and special adaptations to the cold. The fossil distribution is harder to analyse because of the incomplete nature of information gleaned from fossils. The issues canvassed include evolution, geological and climate changes. The conclusion is that the distribution of fossil and living giant penguins require different explanations.