Exhibit 12.1

CSG Systems International, Inc.

Computation of Ratio of Earnings to Fixed Charges

(in thousands, except ratios)

	Years ended December 31,											Three months ended March 31,
	2000		2001		2002		2003(1)			2004(2)		2005
Income (loss) from continuing operations before income taxes	$	145,203	$	183,442	$	87,544	$	(48,460	)	$	69,206	$	14,067
Fixed Charges:
Interest on long-term and short-term debt including amortization of debt expense		5,808		3,038		14,033		14,717			10,334		1,915
Interest element of rentals		3,040		4,240		11,600		9,720			7,936		1,978
Total fixed charges		8,848		7,278		25,633		24,437			18,270		3,893
Earnings before income taxes and fixed charges	$	154,051	$	190,720	$	113,177	$	(24,023	)	$	87,476	$	17,960
Ratio of earnings to fixed charges		17.41		26.21		4.42		—			4.79		4.61

(1) As a result of the Comcast arbitration ruling, we recognized a loss from continuing operations before income taxes for the year ended December 31, 2003. The amount of the coverage deficiency for the historical year ended December 31, 2003 was $48.5 million.

(2) Excludes the write-off of unamortized deferred financing costs of $6.6 million resulting from the repayment of our outstanding indebtedness under our then-existing credit facility in June 2004.