Gordon Christiansen, managing director of LGS, which supplies in-house creative departments with colour printing and proofing systems, said that the two businesses were "highly complementary".
"This [acquisition] will accelerate our growth in the pre-media segment, while complementing the company's successful organic growth strategy," he added.
TPI, which is a distributor and integrator of workflow and DAM software from the likes of Dalim and Xinet, will work with LGS to offer customers a complete workflow and colour management solution.
Steve Emerson, director at TPI, said: "I'm excited to see the hard work of the team soon extended. The combination of TPI and LGS means we can provide additional services to clients as well as expand the reach of our expertise."
According to the two companies, the deal will benefit clients through the combination of customised workflow management integrated with colour proofing and output systems.
Lee Williams, technical director at LGS, which sells and supports kit from Canon, Xerox, HP and Epson, said: "LGS has long been a supporter of flexible software such as Dalim and Xinet.
"TPI operates in a niche market integrating and supporting workflow management software utilised by creative professionals. LGS will continue to support Dalim and Xinet technology and expand our commitment to existing LGS clients."
LGS acquired TPI from TAG chief executive Steve Parish, who is understood to have invested in the business in order to save it from insolvency following its ill-fated merger with Newcastle Computer Services (NCS) in 2007.