In classical stereology we apply geometrical probes in 3-D by cutting the object physically into thin sections and then applying a 2-D grid to the section. Depending on the dimensionality of the grid (Points, lines, surfaces) we can obtain unbiased estimates of volume surface and length. This process necessarily destroys the specimen. With the confocal microscope we have a tool which can non-destructively interrogate the microstructure of objects with geometrical probes of between 0- and 3-dimensions, repeatedly if indicated. This is leading to new ideas in the field of stereology, in particular with the measurement of 0-dimensional properties such as particle number, spatial distribution and connectivity. These ideas and key references are given herein.