A hydro-mechanical continuously variable transmission ("HMCVT") of the type having: a. a transmission input; b. a main shaft; c. a first planetary gear set, comprising: i) a first ring gear; ii) a first sun gear; and, iii) a first carrier; d. a first transfer gear; e. a second transfer gear; f. a third transfer gear; g. a fourth transfer gear; h. a hydraulic branch, comprising: i) a first hydraulic pump coupled to said transmission input through said first transfer gear and said second transfer gear; and, ii) a first hydraulic motor coupled to said first hydraulic pump, wherein an output of said hydraulic branch is transferred to said main shaft through said fourth transfer gear and said third transfer gear; j. a mechanical branch comprising said main shaft wherein said mechanical branch is coupled to said transmission input and to said third transfer gear, wherein said transmission input is coupled to one of said first ring gear, said first sun gear, and said first carrier; and, wherein said hydraulic branch is coupled to a second one of said first ring gear, said first sun gear, and said first carrier; and, wherein said mechanical branch is coupled to a third one of said first ring gear, said first sun gear, and said first carrier; and, wherein the output of said hydraulic branch and the output of said mechanical branch are combined at said third transfer gear and said fourth transfer gear such that a percentage of power arising from said hydraulic branch decreases as said main shaft increases in speed; and, wherein said HMCVT is characterized as further comprising: k. a two-speed shifting planetary gear set comprising a second sun gear, a second ring gear, and a second carrier, wherein two speed shifting planetary gear set transfers the power combined at third transfer gear and fourth transfer gear to an output shaft; l. a low-speed clutch or brake; and, m. a high-speed clutch, wherein said low-speed shifting clutch or brake is operative to hold said second ring gear fixed for low-speed operation; and, wherein said two-speed shifting planetary gear set and said high-speed clutch are operative to create a 1:1 gear-ratio for high-speed operation. a. a transmission input; b. a main shaft; c. a first planetary gear set, comprising: i) a first ring gear; ii) a first sun gear; and, iii) a first carrier; i) a first ring gear; ii) a first sun gear; and, iii) a first carrier; d. a first transfer gear; e. a second transfer gear; f. a third transfer gear; g. a fourth transfer gear; h. a hydraulic branch, comprising: i) a first hydraulic pump coupled to said transmission input through said first transfer gear and said second transfer gear; and, ii) a first hydraulic motor coupled to said first hydraulic pump, wherein an output of said hydraulic branch is transferred to said main shaft through said fourth transfer gear and said third transfer gear; i) a first hydraulic pump coupled to said transmission input through said first transfer gear and said second transfer gear; and, ii) a first hydraulic motor coupled to said first hydraulic pump, wherein an output of said hydraulic branch is transferred to said main shaft through said fourth transfer gear and said third transfer gear; j. a mechanical branch comprising said main shaft wherein said mechanical branch is coupled to said transmission input and to said third transfer gear, wherein said transmission input is coupled to one of said first ring gear, said first sun gear, and said first carrier; and, wherein said hydraulic branch is coupled to a second one of said first ring gear, said first sun gear, and said first carrier; and, wherein said mechanical branch is coupled to a third one of said first ring gear, said first sun gear, and said first carrier; and, wherein the output of said hydraulic branch and the output of said mechanical branch are combined at said third transfer gear and said fourth transfer gear such that a percentage of power arising from said hydraulic branch decreases as said main shaft increases in speed; and, wherein said HMCVT is characterized as further comprising: wherein said transmission input is coupled to one of said first ring gear, said first sun gear, and said first carrier; and, wherein said hydraulic branch is coupled to a second one of said first ring gear, said first sun gear, and said first carrier; and, wherein said mechanical branch is coupled to a third one of said first ring gear, said first sun gear, and said first carrier; and, wherein the output of said hydraulic branch and the output of said mechanical branch are combined at said third transfer gear and said fourth transfer gear such that a percentage of power arising from said hydraulic branch decreases as said main shaft increases in speed; and, wherein said HMCVT is characterized as further comprising: k. a two-speed shifting planetary gear set comprising a second sun gear, a second ring gear, and a second carrier, wherein two speed shifting planetary gear set transfers the power combined at third transfer gear and fourth transfer gear to an output shaft; l. a low-speed clutch or brake; and, m. a high-speed clutch, wherein said low-speed shifting clutch or brake is operative to hold said second ring gear fixed for low-speed operation; and, wherein said two-speed shifting planetary gear set and said high-speed clutch are operative to create a 1:1 gear-ratio for high-speed operation.