Herbig-Haro objects were discovered 50 years ago, and during this half century they have developed from being mysterious small nebulae to be­ coming an important phenomenon in star formation. Indeed, HH flows are now recognized not only as fascinating astrophysical laboratories involving shock physics and chemistry, hydrodynamics and radiation processes, but it has gradually been realized that HH flows hold essential clues to the birth and early evolution of low mass stars. IAU Symposium No. 182 on Herbig-Haro Flows and the Birth of Low Mass Stars were held from January 20 to 24, 1997 in Chamonix in the french alps. A total of 178 researchers from 26 countries met to discuss our present level of understanding of Herbig-Haro flows and their relation to disk accretion events and T Tauri winds and other outflow phenomena like molecular outflows, embedded molecular hydrogen flows and radio jets. The present book contains the manuscripts from the oral contributions of the symposium. The poster papers were printed in a separate volume Low Mass Star Formation - from Infall to Outflow, edited by Fabien Malbet and Alain Castets, which was distributed at the beginning of the meeting. Together these two books document the vigorous state and the scientific appeal which research into Herbig-Haro flows and related issues in star formation enjoys today, observationally as well as theoretically.

I. Herbig-Haro Objects, H2 Flows and Radio Jets.- 50 Years of Herbig-Haro Research.- HST Observations of the L1551 IRS5 Jet.- Giant Herbig-Haro Flows.- Herbig-Haro Objects in the Orion Nebula Region.- Spectroscopic Properties of Herbig-Haro Flows.- Spectroscopic Signatures of Microjets.- The Ionization State along the Beam of Herbig-Haro Jets.- Thermal Radio Jets.- Molecular Hydrogen Emission in Embedded Flows.- Turbulent Mixing Layers in Herbig-Haro and Embedded H2 Jets.- Far-IR Spectrophotometry of HH Flows with the ISO Long-Wavelength Spectrometer.- II. The Physics and Chemistry of Molecular Outflows.- Observational Properties of Molecular Outflows.- The Molecular Outflow and CO Bullets in HH 111.- Shock Chemistry in Bipolar Molecular Outflows.- Models of Bipolar Molecular Outflows.- The Physics of Molecular Shocks in YSO Outflows.- The Physical and Chemical Effects of C-Shocks in Molecular Outflows.- Herbig-Haro Objects as Searchlights for Dense Cloud Chemistry.- III. Theoretical Models.- Protostellar X-Rays, Jets, and Bipolar Outflows.- Energetics, Collimation and Propagation of Galactic Protostellar Outflows.- Numerical Simulations of Jets from Accretion Disks.- Asymptotic Structure of Rotating MHD Winds and Its Relation to Wind Boundary Conditions.- Hydrodynamic Collimation of YSO Jets.- The Class 0 Outflow Hammered Out?.- Numerical Simulations of Optical Knots in YSO Outflows.- Asymmetric Modes of the Kelvin-Helmholtz Instability in Protostellar Jets.- Kelvin-Helmholtz Instabilities and the Emission Knots in Herbig-Haro Jets.- On the Energetics and Momentum Distribution of Bow Shocks and Colliding Winds.- IV. Disks, Winds, and Magnetic Fields.- Hubble Space Telescope Imaging of the Disks and Jets of Taurus Young Stellar Objects.- Disks and Outflows as seen fromthe IRAM Interferometer.- NMA Imaging of Envelopes and Disks around Low Mass Protostars and T Tauri Stars.- The Observational Evidence for Accretion.- The Radiative Impact of FU Orionis Outbursts on Protostellar Envelopes.- Properties of the Winds of T Tauri Stars.- Magnetospherically Mediated Accretion in Classical T Tauri Stars.- Jets, Disk Winds, and Warm Disk Coronae in Classical T Tauri Stars.- Thermal Structure of Magnetic Funnel Flows.- Magnetic Fields of T Tauri Stars.- Evidence for Magnetic Fields in the Outflow from T Tau S.- V. Low- and High-Mass Protostars and Their Environment.- The Evolution of Flows and Protostars.- Circumstellar Molecular Envelopes.- Millimeter Interferometry of Class 0 Sources: Rotation and Infall Towards L1448N.- Water Masers toward Low-Luminosity Young Stellar Objects.- Massive Star Formation: Observational Constraints.- Low-Mass Versus High-Mass Star Formation.- Orion Proplyds and The Eagle's Eggs.- Two-Wind Interaction Models of the Proplyds in the Orion Nebula.- Conference Summary.- List of Participants.- List of Poster Papers.