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 COVINGTON

11) City of Ellensburg

12) CITY OF GIG HARBOR

13) City of Hoquiam

14) CITY OF ISSAQUAH

15) CITY OF KELSO

16) CITY OF KENMORE

17) CITY OF KENT

18) City of La Center

19) CITY OF LAKE FOREST PARK

20) CITY OF LAKEWOOD

21) CITY OF LONGVIEW

22) City of Lynden

23) City of Moses Lake

24) CITY OF MOUNTLAKE TERRACE

25) City of Newcastle

26) CITY OF PORT ORCHARD

27) CITY OF REDMOND

28) CITY OF SEATAC

29) CITY OF TACOMA

30) CITY OF TOPPENISH

31) CLARK COUNTY

32) Consumer Brands Association

33) COWLITZ PUD

34) Economic Alliance Snohomish County

35) Evergreen Forest Stewards

36) FEDEX

37) Food Northwest

38) HIGHLINE COLLEGE

39) INLAND POWER & LIGHT

40) Innovia Foundation

41) Island County

42) Jaguar Transport Holdings LLC

43) LendingTree, LLC

44) Lewis County

45) Lewis PUD 01

46) McCain Foods USA, Inc

47) MGA Home Healthcare Washington LLC

48) North Olympic Legislative Alliance

49) PACIFIC COAST SHELLFISH GROWERS ASSN

50) Pacific Lutheran University

51) Palo Alto Networks

52) PISCES INTERNATIONAL

53) PORT BLAKELY

54) Port of Longview

55) Port of Pasco

56) PRA Group, Inc.

57) Puget Sound & Pacific Railroad

58) RELX INC

59) San Juan County

60) Skagit County

61) SNOHOMISH CO

62) THERMO FISHER SCIENTIFIC, INC.

63) TOTAL WINE & MORE

64) Town of Yacolt

65) WA ASSN OF WHEAT GROWERS

66) WA GRAIN COMMISSION

67) WA OIL MARKETERS ASSN

68) WA POTATO & ONION ASSN

69) WA ST POTATO COMMISSION

70) Washington School Counselor Association

71) Watco

72) Whatcom Co

73) 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: November 27, 2025