High angular resolution observations have provided some valuable information on the circumstellar environment of AGB and post-AGB stars. We review the recent results obtained in this field and focus on observations showing evidence of non-sphericity at different spatial scales (envelope, jets, binarity, maser clumps, stellar ``photosphere'', hot spots, etc.). Such studies provide many informations/constraints not yet fully understood and seldom included in models. Although the available observations are very nice and interesting, they sometimes show limited performances with regards to what is needed to analyse the onset of the winds. We try to show, here, what must be gained to improve our present knowledge.
Asymptotic Giant Branch Stars
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