Exhibit 21.1

SUBSIDIARIES OF REGISTRANT

AS OF OCTOBER 31, 2012

ABM INDUSTRIES INCORPORATED

(*) ABM Janitorial Services, Inc.

ABM Janitorial Services – Mid-Atlantic, Inc.

ABM Janitorial Services – North Central, Inc.

ABM Janitorial Services – Northeast, Inc.

ABM Janitorial Services – Northwest, Inc.

ABM Janitorial Services – South Central, Inc.

Servall Services Inc.

ABM Janitorial Services – Southeast, LLC

ABM Government Services, Inc.**

ABM Industrial Services, Inc.

ABM Services, Inc.

Southern Management ABM, LLC

ABM Janitorial Services Co., Ltd.

Canadian Building Maintenance Company, Ltd.

Supreme Building Maintenance, Ltd.

Diversco, Inc.

OneSource Facility Services, Inc.

OneSource Holdings, LLC

OneSource Servicos de Mexico S.A. de C.V.

FCI Servicos de Mexico S.A. de C.V.

FCI Servisitema S.A. de C.V.

OneSource Painting, Inc.**

ABM Security Services, Inc.

ABM Shared Services, Inc.

Ampco System Parking

Ampco Pacific Airpark, LLC***

Pansini Oakland Associates, LP***

FSP PPM Management, LLC****

Five Star U Street Metropolitan Airport Parking, LLC****

FSP PPM Oakland Airport Management, LLC****

Five Star/Universal Joint Venture****

American Public Services

ATL and Electrical Services**

ATL Services**

ATL Services of the Midwest**

Amtech Energy Services**

Amtech Reliable Elevator Company of Texas**

OneSource Services, LLC

ABM Facility Solutions Group, LLC

Home Performance Enterprises, LLC

GreenHomes Performance Services, LLC

GreenHomes Multi-Family Services, LLC

GreenHomes America, LLC

GreenHomes America, LP***

REEP, Inc.

ABM Government Services, LLC

Linc Government Services Afghanistan Branch, LLC

Linc Government Services Germany GmbH

Ferguson-Williams LLC

FWH, LLC****

TSAY/Ferguson-Williams, LLC****

AFH Services, LLC****

TC&S/Ferguson-Williams, LLC****

J&J/BMAR Joint Venture, LLC****

EML/BMAR Joint Venture, LLC****

EML/BMAR Joint Venture II, LLC****

EML/BMAR Joint Venture III, LLC****

EML/BMAR Joint Venture IV, LLC****

EML/BMAR Joint Venture V, LLC****

EML/BMAR Joint Venture VI, LLC****

EJB Facility Services JV LLC****

Derichebourg/BMAR Joint Venture****

Defense Logistics Solutions, LLC****

ABM Facility Services, Inc.

Linc Facility Services Canada, ULC

DT-Linc, LLC (JV)****

Skyline Management Group, JV****

Trio Facility Management, LLC****

A. Anthony – ABMFS, LLC****

Linc International, Inc.

Linc Facility Services Kuwait, LLC

Linc Facility Services Egypt, LLC

Linc Facility Services UAE, LLC

Linc Facility Services Iraq LLC

Wassl Al-Iraq Project Services & General Contracting LLPC

Linc Facility Services ME, LLC

Linc Facility Services Saudi Arabia, LLC****

Linc Facility Services Egypt, LLC (Egyptian Co.)****

Linc Facility Services, WLL****

Linc Network, LLC

ABM Building & Energy Solutions, Inc.

ABM Building Solutions, LLC

ABM Building Services, LLC

ABM Electrical Power Solutions, LLC

ABM Electrical Power Services, LLC

ABM Health, Inc.

ABM Electrical Network, Inc.

ABM Electrical & Lighting Solutions, Inc.

Sundown Lighting, Inc.

* Subsidiary relationship to Company or to subsidiary parents shown by progressive indentation.

** Inactive companies

*** Limited Partnership

**** Joint Venture