Abstract: This paper summarizes the latest advances in the molecular and genetic analysis of low phosphate (Pi) responses in Arabidopsis thaliana. Emphasis is on the functional involvement of the SUMOylation pathway, several transcription factors involved in low Pi responses, Pi homeostasis regulation and Pi recycling by phospholipases in Pi-starved Arabidopsis. The potential functional relations among the genes identified so far in low-Pi responses in Arabidopsis are also discussed.