Approximately 470 million years ago, plants colonized terrestrial niches, coinciding with the evolution of 3-dimensional growth (3D), an invariable and fundamental feature of all land plants. The acquisition of apical cells that could cleave in three planes, rather than just one or two, allowed plants to develop the characteristics required to successfully survive and reproduce on land. Moreover, diverse morphologies exhibited across the globe are a result of the differential regulation of 3D growth processes. Yet, we know relatively little about how 3D growth is regulated at the genetic level. My group has established Physcomitrium patens as a model system to elucidate the genetic pathways underpinning 3D growth. Although the genetic basis remains somewhat elusive, the 3D developmental trajectory is well characterized in P. patens. A series of highly coordinated asymmetric cell divisions convert an initial cell into a leafy shoot (gametophore) bearing a prominent tetrahedral-shaped apical cell capable of 3D growth; self-renewal and the generation of leaf-like phyllids that wrap around the gametophore in a spiral pattern. Using forward genetics, we have isolated ‘no gametophores’ (nog) mutants that fail to establish and/or maintain 3D growth. Invariably, these mutants cannot orient division planes within emerging buds, and bud development arrests early in development. We continue to identify, and functionally characterize, novel regulators of the 2D to 3D growth transition. Our research aims to answer an overarching and fundamental research question – ‘How is 3D growth regulated and how did it evolve?’