A new model for the initiation of solar coronal mass ejections (CMEs) is proposed, which explains two key properties of CMEs and eruptive flares: (1) magnetic field lines can open toward infinity during an eruption, even down to the photospheric neutral line; and (2) the eruption is driven solely by magnetic free energy stored in a closed, sheared arcade, with the magnetic energy of the closed state being higher than that of the post-eruption open state. The model suggests that CMEs occur in multi-polar topologies, where reconnection between a sheared arcade and neighboring flux systems triggers the eruption. This "magnetic breakout" model involves reconnection that removes unsheared field above the low-lying, sheared core flux near the neutral line, allowing this core flux to burst open. Numerical simulations demonstrate that the model can account for the energy requirements for CMEs. The model implies that the energy for the eruption is stored in the magnetic field, not in gas pressure, and that the energy of the sheared closed state is much higher than the energy of the open state, which is in conflict with the Aly-Sturrock energy limit. However, the model shows that in a multi-flux system, the fully open state is not unique, and the energy of the sheared closed state can be much higher than the minimum open state. The model also explains how the energy difference between the maximum and minimum open states can drive the eruption. The model is supported by numerical simulations that show that the energy of the sheared MHD field greatly exceeds the minimum energy state, and that the energy of the sheared field is much higher than the minimum open state. The model also suggests that the reconnection at the null point is slow, allowing the magnetic energy to rise well above the minimum energy state. The model is consistent with observations of CMEs and eruptive flares, and provides a framework for understanding the initiation of CMEs and flares. The model also suggests that the exact energy equation for the plasma plays a crucial role in determining when an eruption will occur. The model is also consistent with the observation that CMEs are more common in regions with complex magnetic topologies, and that high-latitude CMEs not associated with active regions are slow and similar to the slow solar wind. The model also suggests that fast CMEs are likely due to magnetic breakout, most likely occurring in strong active region fields. The model is supported by numerical simulations that show that the energy of the sheared MHD field greatly exceeds the minimum energy state, and that the energy of the sheared field is much higher than the minimum open state. The model also suggests that the reconnection at the null point is slow, allowing the magnetic energy to rise well above the minimum energy state. The model is consistent with observations of CMEs and eruptive flares, and provides aA new model for the initiation of solar coronal mass ejections (CMEs) is proposed, which explains two key properties of CMEs and eruptive flares: (1) magnetic field lines can open toward infinity during an eruption, even down to the photospheric neutral line; and (2) the eruption is driven solely by magnetic free energy stored in a closed, sheared arcade, with the magnetic energy of the closed state being higher than that of the post-eruption open state. The model suggests that CMEs occur in multi-polar topologies, where reconnection between a sheared arcade and neighboring flux systems triggers the eruption. This "magnetic breakout" model involves reconnection that removes unsheared field above the low-lying, sheared core flux near the neutral line, allowing this core flux to burst open. Numerical simulations demonstrate that the model can account for the energy requirements for CMEs. The model implies that the energy for the eruption is stored in the magnetic field, not in gas pressure, and that the energy of the sheared closed state is much higher than the energy of the open state, which is in conflict with the Aly-Sturrock energy limit. However, the model shows that in a multi-flux system, the fully open state is not unique, and the energy of the sheared closed state can be much higher than the minimum open state. The model also explains how the energy difference between the maximum and minimum open states can drive the eruption. The model is supported by numerical simulations that show that the energy of the sheared MHD field greatly exceeds the minimum energy state, and that the energy of the sheared field is much higher than the minimum open state. The model also suggests that the reconnection at the null point is slow, allowing the magnetic energy to rise well above the minimum energy state. The model is consistent with observations of CMEs and eruptive flares, and provides a framework for understanding the initiation of CMEs and flares. The model also suggests that the exact energy equation for the plasma plays a crucial role in determining when an eruption will occur. The model is also consistent with the observation that CMEs are more common in regions with complex magnetic topologies, and that high-latitude CMEs not associated with active regions are slow and similar to the slow solar wind. The model also suggests that fast CMEs are likely due to magnetic breakout, most likely occurring in strong active region fields. The model is supported by numerical simulations that show that the energy of the sheared MHD field greatly exceeds the minimum energy state, and that the energy of the sheared field is much higher than the minimum open state. The model also suggests that the reconnection at the null point is slow, allowing the magnetic energy to rise well above the minimum energy state. The model is consistent with observations of CMEs and eruptive flares, and provides a