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In the past decade, an increasing number of plant genomes rang-ing from unicellular alga to trees have been completely sequenced. As the transport of water, nutrients, hormones, and metabolites in aquatic plants could differ from that of non-vascular, vascular or flowering plants, this rich resource has the potential to answer many of ourmost urgent questions: How did specific transporters evolve as early plants adapted to dry land? Does the evolution of transporters in monocot plants differ from that in dicots? What are the orthologs in food and energy crops of critical trans-porters characterized in model plants? Can we infer functions or membrane localization from phylogeny? Phylogenetic analyses of transport proteins will shed light on these questions and poten-tially reveal novel insights for future studies to understand the contribution of transporters in plant nutrition, stress tolerance, biomass production, as well as in signaling and development. We invited the plant biology community to participate in this effort as ∼5 % of Arabidopsis thaliana (and probably other plant) genome encodes proteins with predicted transport roles. The Arabidopsis thaliana genome with 27 thousand protein-coding genes has over a 1000 genes classified as transporters, whereas the genomes of other flowering plants can be 2–7 times larger. In this topic issue, several authors have examined the evolu-tionary history and diversification of a range of transporters and these initial results are yielding surprising insights. Some trans-porter families can be traced to the simplest green plants, includ-ing unicellular Chlamydomonas reinhardtii (Chlorophyta). Thus H+-coupled antiporters like NHX (Chanroj et al., 2012), CAX