Introduction

Diana Carlen is a Vice President at Gordon Thomas Honeywell Governmental Affairs (GTH-GA), the state's largest comprehensive governmental affairs firm. GTH-GA is information-driven and non-partisan. Diana represents a broad group of clients before the state legislature, state agencies, and the executive branch.

Clients

1) 1A Smart Start LLC

2) Bamboo Health

3) Benton County Commissioners

4) Cascade Water Alliance

5) City of Aberdeen

6) City of Airway Heights

7) City of Bainbridge Island

8) City of Battle Ground

9) City of Blaine

10) City of Bothell

11) CITY OF COVINGTON

12) City of Ellensburg

13) CITY OF GIG HARBOR

14) City of Hoquiam

15) CITY OF ISSAQUAH

16) CITY OF KELSO

17) CITY OF KENMORE

18) CITY OF KENT

19) City of La Center

20) CITY OF LAKE FOREST PARK

21) CITY OF LAKEWOOD

22) CITY OF LONGVIEW

23) City of Lynden

24) City of Moses Lake

25) CITY OF MOUNTLAKE TERRACE

26) City of Newcastle

27) CITY OF PORT ORCHARD

28) CITY OF REDMOND

29) CITY OF SEATAC

30) CITY OF TACOMA

31) CITY OF TOPPENISH

32) CLARK COUNTY

33) Consumer Brands Association

34) COWLITZ PUD

35) Economic Alliance Snohomish County

36) Evergreen Forest Stewards

37) FEDEX

38) Food Northwest

39) GOODWILL OF THE OLYMPICS & RAINIER REGION

40) Greater Grays Harbor, Inc

41) Haploos Inc

42) HIGHLINE COLLEGE

43) INLAND POWER & LIGHT

44) Innovia Foundation

45) Island County

46) Jaguar Transport Holdings LLC

47) LendingTree, LLC

48) Lewis County

49) Lewis PUD 01

50) McCain Foods USA, Inc

51) MGA Home Healthcare Washington LLC

52) North Olympic Legislative Alliance

53) PACIFIC COAST SHELLFISH GROWERS ASSN

54) Pacific Lutheran University

55) Palo Alto Networks

56) PISCES INTERNATIONAL

57) PORT BLAKELY

58) Port of Hoodsport

59) Port of Longview

60) Port of Pasco

61) PRA Group, Inc.

62) Puget Sound & Pacific Railroad

63) RELX INC

64) San Juan County

65) Skagit County

66) SNOHOMISH CO

67) SSMCP

68) Team Select Home Care

69) THERMO FISHER SCIENTIFIC, INC.

70) TOTAL WINE & MORE

71) Town of Yacolt

72) WA ASSN OF WHEAT GROWERS

73) WA GRAIN COMMISSION

74) WA OIL MARKETERS ASSN

75) WA POTATO & ONION ASSN

76) WA ST POTATO COMMISSION

77) Washington School Counselor Association

78) Watco

79) Whatcom Co

80) YAKIMA CO

Number of Years as a Lobbyist

6-10 years

Biography

Diana Carlen leads the firm's business and utility practice and has over 20 years of legal and legislative experience. Prior to joining Gordon Thomas Honeywell Governmental Affairs, Diana served as Leadership Counsel to the Senate Republican Caucus. In that role, she also served as the caucus attorney for the following policy issues: energy, natural resources, agriculture, land use, telecommunications and water issues. Prior to working for the Senate, Diana practiced law for several years focusing on land use and environmental issues and also served as a Law Clerk to Chief Justice Gerry Alexander of the Washington State Supreme Court. Diana represents several of the firm's business clients, public utilities, and port clients.

Last Updated: October 21, 2025