The original scheme as worked out in 1936 envisioned that a mixed brigade would be made of 3,700 soldiers. Internal composition was to be as follows: • brigade staff • 4 infantry
battalions. Each battalion was to consist of 4 infantry
companies, 1 machine-gun company and 1
platoon of
mortars. In comparison the regular army division, named "división orgánica", was composed of 2 brigades, each brigade composed of 2 regiments, each regiment composed of 3 battalions • 1 field artillery group. It was to be composed of 4 batteries of medium artillery (usually 75 mm guns) and 1 battery of heavy artillery (usually 105 mm guns). In comparison the regular army division was to consist of 1 regiment of light artillery and 1 regiment of heavy howitzers • 1
cavalry squadron (in alternative versions replaced with motorized infantry). In comparison the regular army division was also to include 1 squadron, on wartime footing enlarged to 1 cavalry regiment • 1
pioneer company. The regular army division was to incorporate 1 battalion of pioneers • 1 motorized
reconnaissance squadron • 1 communication and logistics group. It was to consist of dedicated communication (including radio transmission), intendancy and supply-logistics sub-units • other support sub-units, including a sanitary and medical detachment In terms of manpower the mixed brigade as originally envisioned was in-between a regular army infantry regiment and a regular brigade. In terms of firepower it would have been stronger than a brigade. In most European armies of the late 1930s (which unlike the Spanish army did not feature brigades as fixed divisional units) it would have been comparable to a very strong regiment. In terms of
modus operandi and because of its general autonomy a mixed brigade was somewhat resemblant of a division. ==Implementation problems==