A bone cement mixing and delivery system, the system comprising: a mixer including: a base having a housing that has a mixing chamber for receiving bone cement-forming components, the housing having an exit port that opens out of the mixing chamber; a paddle (126, 126', 126") moveably disposed in the mixing chamber for mixing the components to form bone cement; a piston mounted to the base, the piston being moveable relative in the housing and through the mixing chamber so as to push the cement out through the housing exit port; an electrically actuated drive assembly (120, 150, 192) that is connected to: said paddle (126, 126', 126") to move said paddle in the mixing chamber; and said piston to move said piston through the mixing chamber; and a delivery device, said delivery device having: a reservoir for receiving the bone cement discharged from the mixing chamber, the reservoir having opposed proximal and distal ends, an opening in the proximal end and a delivery port in the distal end; a plunger disposed within the reservoir, the plunger having a head that is configured to move from the opening in the proximal end of the reservoir towards the distal end of the reservoir to drive cement out of the delivery port; characterized in that the reservoir is formed with an entry port located forward of the proximal end of the reservoir, the entry port being separate from the proximal end opening and the delivery port; and a transfer conduit extends from the base housing exit port to the reservoir entry port through which the cement is transferred into the reservoir; and a one-way valve is mounted to the reservoir entry port, said valve configured to allow flow into the reservoir and prevent flow out of the reservoir. a mixer including: a base having a housing that has a mixing chamber for receiving bone cement-forming components, the housing having an exit port that opens out of the mixing chamber; a paddle (126, 126', 126") moveably disposed in the mixing chamber for mixing the components to form bone cement; a piston mounted to the base, the piston being moveable relative in the housing and through the mixing chamber so as to push the cement out through the housing exit port; an electrically actuated drive assembly (120, 150, 192) that is connected to: said paddle (126, 126', 126") to move said paddle in the mixing chamber; and said piston to move said piston through the mixing chamber; and a base having a housing that has a mixing chamber for receiving bone cement-forming components, the housing having an exit port that opens out of the mixing chamber; a paddle (126, 126', 126") moveably disposed in the mixing chamber for mixing the components to form bone cement; a piston mounted to the base, the piston being moveable relative in the housing and through the mixing chamber so as to push the cement out through the housing exit port; an electrically actuated drive assembly (120, 150, 192) that is connected to: said paddle (126, 126', 126") to move said paddle in the mixing chamber; and said piston to move said piston through the mixing chamber; and a delivery device, said delivery device having: a reservoir for receiving the bone cement discharged from the mixing chamber, the reservoir having opposed proximal and distal ends, an opening in the proximal end and a delivery port in the distal end; a plunger disposed within the reservoir, the plunger having a head that is configured to move from the opening in the proximal end of the reservoir towards the distal end of the reservoir to drive cement out of the delivery port; a reservoir for receiving the bone cement discharged from the mixing chamber, the reservoir having opposed proximal and distal ends, an opening in the proximal end and a delivery port in the distal end; a plunger disposed within the reservoir, the plunger having a head that is configured to move from the opening in the proximal end of the reservoir towards the distal end of the reservoir to drive cement out of the delivery port; characterized in that the reservoir is formed with an entry port located forward of the proximal end of the reservoir, the entry port being separate from the proximal end opening and the delivery port; and a transfer conduit extends from the base housing exit port to the reservoir entry port through which the cement is transferred into the reservoir; and a one-way valve is mounted to the reservoir entry port, said valve configured to allow flow into the reservoir and prevent flow out of the reservoir.