The fluorescence microscope is routinely used to study cellular structure i
n many biomedical research laboratories and is increasingly used as a quant
itative assay system for cellular dynamics. One of the major causes of imag
e degradation in the fluorescence microscope is blurring. Deconvolution alg
orithms use a model of the microscope imaging process to either subtract or
reassign out-of-focus blur. A variety of algorithms are now commercially a
vailable, each with its own characteristic advantages and disadvantages. In
this article, we review the imaging process in the fluorescence microscope
and then discuss how the various deconvolution methods work. Finally, we p
rovide a summary of practical tips for using deconvolution and discuss imag
ing artifacts and how to minimize them.