Although Aguinaldo already gave the order to engage in guerilla order in November 1899 after the Philippine Republic's northern forces in Luzon suffered defeat from the U.S. Eighth Army Corps, Malvar still engaged the Americans using conventional warfare during the January 1900 invasion of Batangas. The switch to guerilla warfare only occurred after Batangas had fallen to the Americans and had been occupied.

Synthesized Excerpts from Battle for Batangas, A Philippine province at war. by Glenn Anthony May:

As the Americans were attempting to mop up the remaining units of the Filipino Army in the occupied provinces, the Filipino forces were undergoing a major transformation. Their military organization had been shattered, their troops battered and scattered. Even so, Filipino leaders in the region were not ready to quit. The setbacks could be overcome, the war, they believed, could still be won. To replace the men lost in the recent fighting, they could recruit new men and organize new units. To cope with an enemy that could not be beaten in set-piece encounters, they would turn to unconventional warfare.

Malvar's ability to solve the formidable problems that faced him at the beginning of the guerilla campaign was nothing short of remarkable.

Glenn Anthony May

1) Completed the reorganization of the local force, so badly mauled during the invasion. He placed his colonels – Santiago Rillo, Martin Cabrera, Melecio Bolaños, and others – in charge of specific geographical areas or zones, in which several columns are stationed. Each column commanded by a major, was composed of three or more companies led by captains, and was itself assigned to a designated sector, typically, the geographical limits of a town. Individual companies were responsible for their own areas of operations, usually a few barrios.

Malvar decreed that three new "flying columns" were to be created in Batangas City; he named three trusted subordinates -- Eliseo Claudio, Crisanto Borruel, and Elias Mendoza -- as column commanders, each with the rank of major; and he ordered them to find the necessary soldiers as soon as possible. The three majors swung into action, and in a matter of days, the columns were functioning. The most distinguishing feature of these new units -- and this too was decided by Malvar -- was their decentralization. Borruel's column consisted of four companies, with two stationed in outlying barrios of Batangas City, one in the environs of Ibaan, and the fourth in Taysan. Claudio's column was positioned in barrios of Batangas City, Lobo, and Taysan. The structure of these new organizations reflected their function; hereafter, their principal activities were hiding and harassment.

In the aftermath of these changes, the war in Batangas and the neighboring provinces took on a different character. Although Malvar's men concentrated on hiding, they were always on alert---watching the Americans from a distance, passing on information about their movements to other guerilla units in the vicinity, planning ambushes. And then without warning, they struck, usually in small numbers, and rarely for more than a few minutes.

Malvar's men were signaling to the US Army that the battle for Batangas had only begun.

2) Feeding approximately three thousand troops under his command in Batangas. Although the Filipinos suffered from lack of weapons and ammunition—no more than two-thirds of the Batangueño troops were equipped with rifles and the supply of cartridges were limited—the shortages did not extend to food.

In February 1900, Malvar established a system of taxation in the province, designed to raise the money needed to cover the expenses of his troops. All non-combatants over the age of 14 were required to pay a minimum weekly tax: four curators for single males (Four curators = one real; eight reales = one peso), two for single females, six for married couples. The rich were ordered to contribute according to their means.

After each harvest, landowners were obliged to contribute a tenth of their and corn to the Filipino Army. Malvar instructed local commanders to appoint one man in each barrio to serve as a tax collector, and the collectors were required to turn over the proceeds of their collection to military administrators. The system worked reasonably well, and the troops were well-fed.

3) Fighting the Americans by unconventional means. Approach to guerilla warfare was elegantly simple. Troops were expected to do three things:

• ambush the enemy
• disrupt supply and communications networks
• hide

Most contacts with the enemy were to be brief, most units making contact were to be small, and before launching any ambush, commanders were required to make certain that they stationed men along roads which the enemy might use to send reinforcements and that their own troops had easy access to escape routes.

Operations were designed to annoy the Americans and not produce a decisive battlefield result. Malvar did not want his own forces to absorb heavy losses in them.

For the U.S. soldiers stationed in Batangas, the war was frustrating. The Batangueño forces generally restricted their offensive operations to ambushing small units and escort parties and conducting hit-and-run raids on the American posts. With great regularity, they disrupted the American's communications system by cutting down telegraph wires. Hence, the Americans faced an elusive enemy -- one willing to fight only when he had a decisive advantage and who, when he lacked such an advantage, was content to hide.

During the fifteen-month period February 1, 1900-April 30, 1901, U.S. troops engaged in more than 150 hostile actions in the province of Batangas. First of all, most were initiated by Filipinos; in effect, Malvar's men were dictating the level of fighting at this stage of the campaign. Second, the contacts occurred in virtually every part of the province. In this war without fronts, the Filipinos were apt to strike anywhere; they might be hiding anywhere. Third, almost all of the engagements that occurred in Batangas during these fifteen months were little more than skirmishes--small scale actions that lasted only a few minutes.

Of these skirmishes, the ones started by the Filipinos followed familiar patterns. Generally, one or two companies of Malvar's men attacked a small group of Americans -- an escort party, a wagon train, a scouting party. After firing a few shots, the Filipinos scattered. Also, from time to time, a Filipino unit sneaked into an occupied town, briefly attacked an American garrison and then withdrew.

4) Malvar emphasized maintaining good relations with the civilian population. Column commanders were required to secure the cooperation of the local civil government—the same officials who were chosen in the elections supervised by the US Army—in keeping peace, capturing common criminals, collecting taxes, recruiting soldiers, and procuring weapons. Malvar understood the ability of his troops to resist depended on keeping the support of non-combatants; ensure that the noncombatants would not come to view the demands of the guerillas as unnecessarily burdensome.

Large columns were to be stationed in the vicinity of populous towns, with sufficient resources to provide for their needs, and smaller columns in the vicinity of less densely populated ones.

Commanders were instructed to recruit new troops and collect taxes only from certain designated barrios, lest communities be subjected to exactions from only one command.

“All commanders will make sure,” Malvar wrote, “that the civil authorities are in agreement with the military authorities (and vice versa), avoiding the situation in which anyone suffers loss to his person and family.”

“All commanders and good citizens will ensure that all misunderstandings are resolved because they only weaken the united front and solidarity of interests that are needed for the attainment of our independence.”

5) Malvar placed primary emphasis on small-unit actions, he also mounted large-scale operations from time to time. He believed a periodic large-unit action necessary to gain the attention of the US public and to make them aware of the costs of continued occupation.