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tokens: a spherical explosion triggered inside a rotationally supported torus (presumed to be formed by preceding binary interaction), which results in a collimation of ejecta toward the system’s poles. Frank et al. ( 2018 ), García-Segura et al. ( 2018 ), and Reichardt et al. ( 2018 ) recently discussed the interaction of stellar winds with the debris of a common-envelope episode and how this process might contribute to observed bipolar planetary nebulae. Here we expand on this line of work to show that bipolar morphologies can, instead, arise from the interaction of successive components of equatorial mass loss from the coalescing binary. We analyze numerical simulations of coalescing binaries transitioning from Roche lobe overflow toward the onset of the common-envelope phase. We show that early outflows, contrary to previous theoretical predictions, are bound to the binary system and form a circumbinary torus. Later ejecta, generated just as the secondary object plunges within the envelope of the donor, have larger radial velocities and are unbound. The interaction of unbound ejecta with the bound torus redirects ejecta toward the poles, laying the foundation for the generation of bipolar remnants of stellar coalescence recently reported by Kaminski et al. ( 2018 ). 2. Bipolar Remnants of Stellar Coalescence and Binary Interaction 2.1. Remnants of Galactic Red Novae There is growing evidence that the remnants of galactic luminous red nova outbursts, believed to originate from stellar coalescence, can exhibit bipolar structures. There is strong evidence for a bipolar morphology of V4332 Sgr. We also review the less extensive evidence related to the two other galactic transients that have been studied, V1309 Sco and V838 Mon. Some of the first evidence for bipolar morphologies came from V - and R -band linear polarization measurements of the remnant of V4332 Sgr, which flared in 1994 (Kamiński Tylenda 2011 ). Correcting for the effect of significant unpolarized line emission, Kamiński Tylenda ( 2011 ) estimated continuum polarizations of approximately 40% and 20% for the V and R bands, respectively, and suggested that dust scattering in a bipolar outflow is one of the only morphologies that can produce such high linear polarization in an unresolved source. Spectropolarimetric observations by Kamiński Tylenda ( 2013 ) confirmed Kamiński Tylenda’s ( 2011 ) suggested continuum polarization. Earlier conclusions regarding morphology have recently been strengthened by submillimeter observations, which have offered an opportunity to spatially resolve galactic remnants of stellar-coalescence transients (Kaminski et al. 2018 ). Spatially resolved observations using the ALMA of V4332 Sgr produce a position–velocity diagram that is best modeled with a bipolar molecular outflow with a 60° opening angle (see Figures 5 and 6 of Kaminski et al. 2018 ). The merger of V1309 Sco has been extremely useful in decoding observations of luminous red novae in general.