A Provocative Summary: Is There Any Unified Model for Triggering Active
  Galactic Nuclei ?
  A provocative summary of the conference on "Galaxy Mergers in an Evolving
Universe" is presented. The conference includes the following issues; 1)
Mergers at low redshift, 2) Merger dynamics and numerical simulations, 3)
Mergers in galaxy evolution, 4) Mergers and active galactic nuclei (AGNs), 5)
Mergers at high redshift and submm galaxies, 6) Feedback from starbursts and
AGNs, 6) Chemical evolution of galaxies, and 7) Results from new surveys.
Although there are many important issues related to galaxy mergers and nuclear
activities in galaxies, in this summary, l et us focus on following the
question; {\it Is there any unified model for triggering nuclear activities ?}
Given key observational properties of galaxies with AGNs, a possible unified
model is discussed as an evolutionary model from starbursts to AGNs based on
minor and major mergers between/among galaxies.
