Papers from Session WS28 'Defining a Methodological Approach to Interpret Structural Evidence', AND papers from Sessions C69, C70 and C71 'Archaeometry', presented at the XV UISPP World Congress (Lisbon, 4-9 September 2006). Contents: 1) Defining a methodological approach to interpret structural evidence: an introduction (Fabio Cavulli); 2) Scant Structural Evidences of Mesolithic Sites in High Alpine Regions (Walter Leitner); 3) U-Shaped Scatters: Struggling between Theoretical Models and Archaeological Facts (Matteo Pilati); 4) Unearthing the hearths. Preliminary results on the Takarkori rockshelter fireplaces (Acacus Mts, Libya) (S. Biagetti, G. Poggi, S. di Lernia); 5) Structures d'habitat nord-africaines: la fouille de la rammadiya cotiere holocene de SHM-1 (Hergla, Tunisie) (S. Mulazzani et al.); 6) Infilling processes of large pit features at Catignano - Neolithic (Italy) (Giovanni Boschian, Marta Colombo);"