The publication Demographical changes in the Wielkopolskie Voivodship in years 1999–2006 presents a reach set of information allowing to assess the condition and structure as well as vital statistics and migration of the population since the moment of creation of the Wielkopolskie Voivodship till 2006. A reach collection of indices used to reflect a level of internal diversification of such phenomena in the Wielkopolska region was established. In the review tables major data on the voivodship and changes of values of selected demographical features for powiats in the whole researched period were presented; information for gminas concerning years 1999 and 2006 was also included. The voivodships were also ordered – it enabled to indicate a rank of the Wielkopolska region within the country.