The presentation will provide an introduction to GeoServer own authentication and authorization subsystems. We'll cover the supported authentication protocols, such as from basic/digest authentication and CAS support, check through the various identity providers, such as local config files, database tables and LDAP servers, and how it's possible to combine the various bits in a single comprehensive authentication tool, as well as providing examples of custom authentication plugins for GeoServer, integrating it in a home grown security architecture.We'll then move on to authorization, describing the GeoServer pluggable authorization mechanism and comparing it with proxy based solution, and check the built in service and data security system, reviewing its benefits and limitations.Finally we'll explore an advanced authentication tool called GeoFence, and see how it can plug into GeoServer to provide graphical configuration abilities for use complex authorization rules over data and OGC services, taking into account spatial filters, attribute filters, attribute hiding as well as cropping raster data to areas of interest. Finally we'll show how using LDAP both GeoFence and GeoServer can use a common users database, simplifying administrators job, and provide some real world examples.