It is sometimes wrongly assumed that the expression contrato de comisión refers exclusively to an agreement whereby an employee, agent or representative works solely on commission (trabaja a comisión) rather than receiving a fixed salary or other compensation. In that regard, contrato de comisión has at times been erroneously translated as a “sales commission agreement” or “commission-only agreement.”

But the Spanish Commercial Code’s contrato de comisión doesn’t necessarily denote “working on commission,” but rather is a type of agency agreement in which a principal (comitente) commissions an agent (comisionista) to carry out a specific commercial transaction on his behalf (the comisión). In that regard, the contrato de comisión may be considered the Commercial Code counterpart of the Spanish Civil Code’s contrato de mandato in which a principal (mandante) commissions an agent (mandatario) to perform a specific service (mandato). Depending on the context, both contrato de comisión and contrato de mandato can often be described in English simply as “agency agreements.”

Thus, in many contexts comitente, mandante and principal can generally be translated as “principal,” while comisionista, mandatario, agente and often gestor can be rendered as “agent.” If it is necessary to distinguish between the Commercial Code and Civil Code counterparts, a contrato de comisión might be described as a “commercial agency agreement” or “Commercial Code agency agreement,” while contrato de mandato might be rendered as “Civil Code agency agreement” or an “agency agreement governed by the Civil Code.” And of course, depending on the terms of the contrato de comisión, a comisionista may or may not “work on commission” (trabajar a comisión).

In other respects, contrato de agencia (“agency agreement”) is likewise used in Spain, having been formally defined in the Agency Agreement Act (Ley 12/1992, de 27 de mayo, sobre Contrato de Agencia), which incorporated into Spanish law the provisions of Directive 86/653/EEC of 18 December 1986 on the coordination of the laws of EU Member States relating to self-employed commercial agents.

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This strange, seemingly cryptic expression is defined in the RAE’s Diccionario del Español Jurídico como prórroga del contrato de arrendamiento de fincas rústicas o urbanas que se produce cuando, una vez terminado el contrato hecho por tiempo determinado, permanece el arrendatario disfrutando quince días de la cosa arrendada con aquiescencia del arrendador.* In that regard, reconducción refers specifically to prórroga de un arrendamiento (DLE).

Tácita reconducción has often been translated literally as “tacit renewal,” described as “renewal by default” or, perhaps in more idiomatic English, rendered as “automatic renewal (of a lease).” But it should be noted that all of these translations are actually inaccurate, confusing prórroga (“extension”) with renovación (“renewal”). Thus tácita reconducción more appropriately denotes the “automatic extension” of a lease (if, as indicated in the DEJ’s definition above, fifteen days after the contract expires neither party has given notice of termination to the other).

*Código Civil, arts. 1566-1567.

In Spanish criminal procedure actor civil refers to a party to a criminal proceeding who is seeking compensation for damages for civil liability arising out of the criminal act being tried. In Anglo-American jurisdictions claims for compensation for damages arising from criminal offenses are typically filed in a separate civil suit and, thus, the role of the actor civil in the Spanish criminal process may often be unclear to English-speaking audiences. In brief, in Spain claims for compensation for damages arising during the commission of a crime (reclamación de la responsabilidad civil derivada de la comisión de un delito) are usually tried simultaneously with the prosecution of criminal defendants during criminal proceedings. Actor civil designates the party who enters an appearance in a criminal proceeding to file a claim for damages in what amounts to a civil liability action conducted simultaneously with (or within) a criminal procecution.

Thus, civil and criminal liability may be determined in the same proceeding if the actor civil enters an appearance and asks to be acknowledged as a party to the criminal proceedings as a plaintiff claiming damages based on the same incident for which a conviction for criminal liability is being sought (la parte solicita que se la tenga por personada en el procedimiento en calidad de actora civil). And in perhaps most cases the victim and and person seeking civil redress are the same.

Actor civil has often been rendered literally as “civil plaintiff” or “civil claimant,” translations that perhaps fail to reflect the fact that the expression actually denotes a party to a criminal proceeding. And, indeed, since this “civil action within a criminal trial” concept will perhaps be foreign to English-speaking audiences, actor civil may require a more detailed descriptive translation such as “party claiming civil damages in a criminal proceeding.” In other respects, the civil claim heard during a criminal trial is often referred to as a proceso civil acumulado, precisely because it is, in effect, a civil action joined or consolidated with (within) a criminal procecution.

Read more here: Víctor Moreno Catena and Valentín Cortés Domínguez. “El llamado ‘actor civil’ en el proceso penal.” Derecho Procesal Penal. Valencia: Tirant lo Blanch, 2005, p. 125 ff.