Petitions were deeply material objects, despite the era’s idealized fiction of the frictionless lord–vassal encounter of wills. This chapter describes how sixteenth-century subjects managed to send their petitions to the royal court, through a daunting and often informal network of couriers. These agents moved petitions, helped and hindered by weather and geography, mastering ocean currents, perilous winds, riverine systems, and mountain paths. Here, the labor contributions of non-Spaniards was highly evident, as Indigenous communities, Afro-descendant rowers and muleteers, and others dominated many of the empire’s most daunting and crucial routes. Many sovereign indigenous and Afro-descendant subjects also sabotaged this mail system from the outside, sometimes in conjunction with British pirates and others. This chapter describes how imperial denizens coped with such sabotage, not least internal interference. It also describes the weakness of the official postal system, the supremacy of merchant couriers, the consequences of antipiracy armadas, and express services. It highlights the complex iniquities and limited successes of this dialogue, revealing that, despite constant obstacles and against all odds, the empire’s communications system – even though slow and often inconsistent – preserved the fiction of vassal–ruler dialogue.