Ribosomopathies are a diverse subset of diseases caused by reduced expression of, or mutations in, factors necessary for making ribosomes, the protein translation machinery in the cell. Despite the ubiquitous need for ribosomes in all cell types, ribosomopathies manifest with tissue-specific defects and sometimes increased cancer susceptibility, but few treatments target the underlying cause. By highlighting new research in the field, we review current hypotheses for the basis of this tissue specificity. Based on new work, we broaden our understanding of the role of ribosome biogenesis in diverse tissue types throughout embryonic development. We also pose the question of whether previously described human conditions such as aging can be at least partially attributed to defects in making ribosomes. Ribosomopathies are disorders of making ribosomes that manifest in afflicted humans with tissue-specificity.Several new ribosomopathies have recently been discovered, helping to reveal the link between ribosome biogenesis and human development.The specialized ribosomes hypothesis states that the tissue-specific defects of ribosomopathies are due to ribosome heterogeneity caused by changes in ribosomal protein composition or modification, rRNA composition or modification, or accessory protein binding.The ribosome concentration hypothesis states that the tissue-specific defects of ribosomopathies are due to changes in mRNA translation as a consequence of reduced ribosome number.Dysregulation of nucleolar activity is associated with aging and neurodegeneration, suggesting that these disorders may perhaps also be ribosomopathies.