We characterized membranes with chloroplast ribosomes during chloroplast development (using the yellow-in-the-dark 1 mutant) and carried out proteomic analyses of two distinct membrane types as translation platforms for chloroplast ribosomes. The results support roles of “low-density membrane” as a platform for preliminary stages of translation and of a denser “chloroplast translation membrane” as a platform for ongoing translation. These roles are based on the proteomes of these membranes, which include proteins in translation, photosystem biogenesis and the biosynthesis of chlorophyll and correlations of their relative levels and the translational status of the chloroplast before, during and after chloroplast differentiation.