Plant cells exchange developmental signals, distribute nutrients and ribonucleoprotein complexes through dynamic intercellular channels termed plasmodesmata (PD). Multidisciplinary investigations over the last decade have provided evidence that plasmodesmatal regulation is critical to various basic plant functions, such as development, host-pathogen interactions, and systemic RNA-silencing. This review highlights the cell-to-cell transport of micro- and macromolecules via PD during embryo and seedling growth.