  We hereby consider the problem of detectability of macro-engineering projects
over interstellar distances, in the context of Search for ExtraTerrestrial
Intelligence (SETI). Freeman J. Dyson and his imaginative precursors, like
Konstantin Tsiolkovsky, Olaf Stapledon or John B. S. Haldane, suggested
macro-engineering projects as focal points in the context of extrapolations
about the future of humanity and, by analogy, other intelligent species in the
Milky Way. We emphasize that the search for signposts of extraterrestrial
macro-engineering projects is not an optional pursuit within the family of
ongoing and planned SETI projects; inter alia, the failure of the orthodox SETI
thus far clearly indicates this. Instead, this approach (for which we suggest a
name of "Dysonian") should be the front-line and mainstay of any cogent SETI
strategy in future, being significantly more promising than searches for
directed, intentional radio or microwave emissions. This is in accord with our
improved astrophysical understanding of the structure and evolution of the
Galactic Habitable Zone, as well as with the recent wake-up call of Steven J.
Dick to investigate consequences of postbiological evolution for astrobiology
in general and SETI programs in particular. The benefits this multidisciplinary
approach may bear for astrobiologists, evolutionary theorists and
macro-engineers are also briefly highlighted.
