Supersymmetry dictates that the moduli space of Calabi-Yau 3-fold compactifications of type II superstring theory is an ordinary (commutative) space. However when one uses D-brane probes to measure the moduli of a particular compactification, one must break this supersymmetry. Using perturbative string theory we show that the measurement of any modulus affects other moduli, leading to an uncertainty principle and hence noncommutativity on moduli space. Furthermore we see that this effect only applies to measurements of moduli in finite regions of space. ©2002 American Institute of Physics.