In the constitution of ancient Rome, prorogatio was the extension of a commander's imperium beyond the one-year term of his magistracy, usually that of consul or praetor. Prorogatio developed as a legal procedure in response to Roman expansionism and militarization; the number of annexed territories and theaters of operations outgrew the number of elected officials available to take on military and administrative duties.

In the constitution of ancient Rome, prorogatio was the extension of a commander's imperium beyond the one-year term of his magistracy, usually that of consul or praetor. Prorogatio developed as a legal procedure in response to Roman expansionism and militarization; the number of annexed territories and theaters of operations outgrew the number of elected officials available to take on military and administrative duties.