The United Pentecostal Church International (UPCI) is a Christian denomination that practices Pentecostalism. There are several synonyms that may be used to refer to this organization, including: - UPC - Pentecostal church - Oneness Pentecostal church - Apostolic church - Holiness church The UPCI is distinguished by its beliefs in the oneness of God, the importance of baptism by immersion in Jesus' name, and the experience of receiving the Holy Spirit with speaking in tongues as evidence. It has a strong commitment to evangelism and missions and operates Bible colleges, publishing houses, and media ministries. With over 4 million members and churches in over 200 countries, the UPCI is a significant player in the global Pentecostal movement.