Experimental evidence has shown that both homeostatic and Hebbian synaptic plasticity can be expressed presynaptically as well as postsynaptically. In this review, we discuss some of the functional consequences of this diversity in expression loci. In particular, using a biologically tuned model of spike-timing-dependent plasticity (STDP) we show that a combination of both pre- and postsynaptic components leads to 1) more reliable receptive fields, 2) rapid recovery of forgotten information, 3) and reduced response latencies, compared to a model with postsynaptic expression only. The diversity of expression of synaptic plasticity thus has important functional consequences. We propose that a considerable research effort is needed to better elucidate how the specific locus of expression of homeostatic and Hebbian plasticity alters network computations.