Stripped-envelope core-collapse supernovae (i.e., SNe of Type IIb, Ib,
Ic and broad-lined Ic) are supernovae whose massive
progenitors have been stripped of progressively larger amounts of
their hydrogen and helium envelopes. While the SNe Ic-bl associated
with long Gamma Ray Bursts (GRBs) have been studied in detail, the
full range of properties of normal or broad-lined SNe is not known,
nor their dominant progenitor channel and the productions conditions that
lead to different kinds of explosions in massive stars.
Observations of stipped SNe yield vital clues about the explosion
properties of massive stars (e.g., explosion geometry) as well as their size and make-
up, and set the foundation for excluding contaminants in high-z SN Ia searches and 
for identifying exotic transients in current and future innovative surveys. 

Here I will review observations of a number of intriguing recent
events (e.g., SN 2008D, SN 2008ax) as well as the statistical
properties of a large sample of stripped SNe, focusing on early-time
and late-time optical spectra. I will also briefly mention the most
recent results on SN environments, specifically on measured metallities, and what 
they may tell us about the progenitors of stripped SNe.