The domain "assessment of existing timber structures" has seen increased interest and gained application in practice over the last years. The objective of this publication is to provide the reader with a collection of applicable assessment methods which have been evaluated by a group of experts with regard to the following objectives:- What can be determined / what can not be determined?- How exact and valid are the results (e.g. degree and size of damage; local/global qualitative/quantitative results)?- How complex and time consuming is its application (on-site, (non-) destructive)?Since each method allows only assessing certain types of damages, it becomes necessary to combine different methods to derive a full picture about the residual performance of the structure. Against this background, common approaches towards the assessment of timber structures are given, including information on possible combinations of methods depending on the phase/depth of the assessment.