EXHIBIT 99.1

FOR IMMEDIATE RELEASE

FIRSTSERVICE ANNOUNCES SECOND QUARTER RESULTS AND UPDATES
OUTLOOK FOR BALANCE OF FISCAL YEAR

TORONTO, Ontario, October 21, 2003 — FirstService Corporation (Nasdaq: FSRV; TSX: FSV) today reported net earnings of $9.1 million and diluted earnings per share of $0.63 for its second quarter ended September 30, 2003, up from $8.9 million and $0.61 in the same period one year ago (all amounts are in US dollars).

Revenues for the quarter were $166.5 million, an increase of 15% over the same period one year ago. Earnings before minority interest, income taxes, interest, depreciation and amortization ("EBITDA") were $21.4 million, an increase of 1% over the prior year period. Canadian operations accounted for approximately 30% of the quarter's revenues. During the quarter, the Canadian dollar was 13% stronger relative to the US dollar than during the same period a year ago. Had the exchange rate been held constant at the prior year's rate, consolidated revenues would have been approximately $5.8 million lower and consolidated EBITDA would have been unchanged.

On a year-to-date basis, revenues were up 11% to $324.3 million while EBITDA was $38.5 million versus $39.7 million in the prior year period. Net earnings were $15.6 million compared to $16.3 million in the prior year period.

Operating cash flow for the six months ended September 30, 2003 was $24.0 million, 23% higher than the prior year period, which enabled the Company to reduce debt significantly. At September 30, 2003, total debt, net of cash, was $138.9 million, a reduction of $14.4 million relative to March 31, 2003.

FirstService Corporation is a North American leader in the rapidly growing service sector, providing services to commercial and residential customers in the following four areas: Residential Property Management; Integrated Security Services; Consumer Services; and Business Services, including customer support and fulfilment and business process outsourcing.

SEGMENTED OPERATING RESULTS

The Company's largest segment, Residential Property Management, reported quarterly revenues of $66.8 million, up 12% over the prior year period, of which 3% was attributable to acquisitions completed during the past twelve months. The segment generated EBITDA of $6.0 million, also up 12% relative to the second quarter of last year. The EBITDA margin of 9.0% was unchanged from the prior year period.

Second quarter revenues in Consumer Services grew to $34.0 million, up 20% versus the same period a year ago, 4% of which was attributable to California Closets "branchise" acquisitions completed during the past twelve months. EBITDA was $9.6 million, up from $9.2 million in the second quarter of last year. Consistent with the trend reported in the first quarter, the EBITDA margin experienced a contraction compared to last year, but remained strong at 28.4%, primarily as a result of mix change due to an increased proportion of Company-owned revenues in the segment.

Integrated Security Services revenues were up 17% relative to the prior year quarter, to $29.5 million. The segment generated EBITDA of $2.2 million, up 11% from the $2.0 million reported in the prior year period. The EBITDA margin was 7.5% versus 7.9% reported in the prior year period primarily due to the mix impact of

lower systems sales relative to total sales in the segment's Canadian operations. The EBITDA margin was up from 6.9% in the first quarter.

Revenues in Business Services were $36.1 million, an increase of 13% over the prior year period. After adjusting for the impact of foreign exchange, internal growth was 5%. EBITDA for the quarter was $5.2 million versus $5.8 million in the same period last year. On a year-over-year basis, foreign exchange had a nominal effect on EBITDA because certain customers are billed for services in US dollars with corresponding costs in Canadian dollars. The EBITDA comparison also reflects lower capacity utilization in the fulfillment operations and recent new client wins, which carry implementation costs and lower margins.

UPDATED OUTLOOK

Based on the operating results achieved during the first two quarters and the recently announced acquisitions, the Company is updating its outlook for the year ending March 31, 2004, initially presented on May 14, 2003, as follows:

*Note: Revenues and earnings from acquisitions completed after today's date but before March 31, 2004 will be incremental to these amounts. The updated outlook assumes an exchange rate of US$0.7500 per Cdn$1.0000 and that interest rates remain unchanged from today's rates.

CONFERENCE CALL

FirstService will be holding a conference call on Tuesday, October 21 at 2:00 pm Eastern Time to discuss results for the second quarter as well as the outlook for the remainder of fiscal 2004. The call will be simultaneously web cast and can be accessed live or after the call at www.firstservice.com in the "Investor Relations / News Releases" section.

FORWARD-LOOKING STATEMENTS

Certain statements included in this release constitute "forward-looking statements" within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. Such forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause the actual results, performance or achievements of the Company, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Such factors include, among others, the following: general economic and business conditions, which will, among other things, impact demand for the Company's services, service industry conditions and capacity; the ability of the Company to implement its business strategy, including the Company's ability to acquire suitable acquisition candidates on acceptable terms and successfully integrate newly acquired businesses with its existing businesses; changes in or the failure to comply with government regulations (especially safety and environmental laws and regulations); and other factors which are described in the Company's filings with the Securities and Exchange Commission.

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FIRSTSERVICE CORPORATION
Condensed Consolidated Statements of Earnings
(in thousands of US dollars, except per share amounts)
(unaudited)

Note to the Condensed Consolidated Statements of Earnings

        EBITDA is defined as net earnings before minority interest share of earnings, income taxes, interest, depreciation and amortization. EBITDA excludes income taxes and interest, both of which are charges that require cash settlement. EBITDA is not a recognized measure for financial statement presentation under United States generally accepted accounting principles ("US GAAP"). The most directly comparable US GAAP measure is operating earnings. Operating earnings takes into account depreciation and amortization expenses, while EBITDA does not. Management utilizes EBITDA as a measure to assess the performance of its operations, for employee compensation purposes, and within its debt covenants with its lenders. The Company believes EBITDA is a reasonable measure of operating performance because of the low capital intensity of its service operations. The Company believes EBITDA is a financial metric used by many investors to compare companies, especially in the services industry, on the basis of operating results and the ability to incur and service debt.

Segmented Revenues and EBITDA
(in thousands of US dollars)
(unaudited)

Condensed Consolidated Balance Sheets
(in thousands of US dollars)
(unaudited)

Condensed Consolidated Statements of Cash Flows
(in thousands of US dollars)
(unaudited)

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