The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
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hours per response: 23.8
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
3m Co COM 88579Y101 1,084 6,951 SH   SOLE NONE 0 0 6,951
Abbott Labs COM 002824100 1,960 21,442 SH   SOLE NONE 0 0 21,442
Abbvie Inc COM 00287Y109 1,511 15,394 SH   SOLE NONE 0 0 15,394
Alphabet Cl A CAP STK CL A 02079K305 3,050 2,151 SH   SOLE NONE 365 0 1,786
Alphabet Cl C CAP STK CL C 02079K107 3,338 2,361 SH   SOLE NONE 1,014 0 1,347
Altria Group Inc COM 02209S103 401 10,211 SH   SOLE NONE 0 0 10,211
Amazon.Com COM 023135106 6,169 2,236 SH   SOLE NONE 965 0 1,271
American Tower Corp COM 03027X100 5,951 23,018 SH   SOLE NONE 7,080 0 15,938
American Water Works COM 030420103 3,371 26,203 SH   SOLE NONE 8,470 0 17,733
Ametek Inc COM 031100100 2,659 29,755 SH   SOLE NONE 12,745 0 17,010
Amgen Inc COM 031162100 873 3,701 SH   SOLE NONE 0 0 3,701
Apple Computer Inc COM 037833100 8,981 24,619 SH   SOLE NONE 4,238 0 20,381
At&t Corp Com New COM 00206R102 279 9,245 SH   SOLE NONE 0 0 9,245
Berkshire Hathaway Class B New CL B NEW 084670702 1,535 8,601 SH   SOLE NONE 1,195 0 7,406
Blackrock Inc. COM 09247X101 4,028 7,404 SH   SOLE NONE 2,705 0 4,699
Booking Hldgs Inc COM 09857L108 358 225 SH   SOLE NONE 0 0 225
Bright Horizons Family COM 109194100 1,698 14,490 SH   SOLE NONE 5,200 0 9,290
Bristol Myers Squibb Co COM 110122108 246 4,183 SH   SOLE NONE 0 0 4,183
CME Group COM 12572Q105 3,382 20,805 SH   SOLE NONE 7,990 0 12,815
Cisco Systems Inc COM 17275R102 717 15,374 SH   SOLE NONE 2,496 0 12,878
Comcast Corp New Cl A CL A 20030N101 351 9,006 SH   SOLE NONE 0 0 9,006
Costco COM 22160K105 224 740 SH   SOLE NONE 0 0 740
Danaher Corp COM 235851102 6,167 34,876 SH   SOLE NONE 11,938 0 22,938
Disney Walt Co Holding Co COM DISNEY 254687106 296 2,653 SH   SOLE NONE 0 0 2,653
Dover Corp COM 260003108 2,460 25,477 SH   SOLE NONE 8,760 0 16,717
Ecolab Inc. COM 278865100 3,989 20,049 SH   SOLE NONE 7,158 0 12,891
Equinix Inc COM 29444U700 3,139 4,470 SH   SOLE NONE 1,645 0 2,825
Exxon Mobil Corp COM 30231G102 570 12,743 SH   SOLE NONE 1,200 0 11,543
Facebook CL A 30303M102 450 1,982 SH   SOLE NONE 304 0 1,678
Fair Isaac Corp. COM 303250104 2,531 6,054 SH   SOLE NONE 2,120 0 3,934
Fidelity National Informationn COM 31620M106 2,870 21,402 SH   SOLE NONE 8,734 0 12,668
First Republic Bank San Franci COM 33616C100 710 6,698 SH   SOLE NONE 500 0 6,198
Fiserv Inc Wis COM 337738108 3,004 30,775 SH   SOLE NONE 11,572 0 19,203
Genuine Parts Co COM 372460105 335 3,854 SH   SOLE NONE 0 0 3,854
Heico Corp. COM 422806109 1,356 13,609 SH   SOLE NONE 6,580 0 7,029
Home Depot Inc COM 437076102 2,114 8,438 SH   SOLE NONE 0 0 8,438
Idexx Laboratories Inc COM 45168D104 3,731 11,300 SH   SOLE NONE 5,075 0 6,225
Illumina Inc COM 452327109 3,482 9,402 SH   SOLE NONE 4,095 0 5,307
Intel Corp COM 458140100 273 4,557 SH   SOLE NONE 0 0 4,557
JP Morgan Chase COM 46625H100 6,978 74,189 SH   SOLE NONE 10,256 0 63,933
Johnson & Johnson Com COM 478160104 3,312 23,548 SH   SOLE NONE 7,785 0 15,763
MSCI COM 55354G100 1,978 5,925 SH   SOLE NONE 2,095 0 3,830
Markel COM 570535104 1,765 1,912 SH   SOLE NONE 622 0 1,290
Marketaxess Holdings COM 57060D108 1,773 3,540 SH   SOLE NONE 1,430 0 2,110
Massimo Corporation COM 574795100 2,599 11,401 SH   SOLE NONE 4,500 0 6,901
Mastercard Inc. CL A 57636Q104 7,038 23,801 SH   SOLE NONE 6,725 0 17,076
Medtronic Inc SHS G5960L103 471 5,138 SH   SOLE NONE 0 0 5,138
Merck & Co Inc New Com COM 58933Y105 901 11,652 SH   SOLE NONE 0 0 11,652
Microsoft Corp Com COM 594918104 3,465 17,026 SH   SOLE NONE 3,454 0 13,572
Netflix, Inc COM 64110L106 3,640 8,000 SH   SOLE NONE 3,645 0 4,355
Nike Inc CL B 654106103 689 7,030 SH   SOLE NONE 0 0 7,030
Paycom Software Inc COM 70432V102 2,428 7,840 SH   SOLE NONE 2,560 0 5,280
Pepsico Inc COM 713448108 406 3,067 SH   SOLE NONE 0 0 3,067
Pfizer Inc Com COM 717081103 490 14,999 SH   SOLE NONE 890 0 14,109
Philip Morris International COM 718172109 514 7,337 SH   SOLE NONE 0 0 7,337
Price T Rowe Group Inc. COM 74144T108 538 4,356 SH   SOLE NONE 0 0 4,356
Procter & Gamble Co COM 742718109 1,686 14,100 SH   SOLE NONE 827 0 13,273
Roper Technologies COM 776696106 5,646 14,541 SH   SOLE NONE 5,119 0 9,422
Royal Dutch Shell Class A SPONS ADR A 780259206 967 29,582 SH   SOLE NONE 0 0 29,582
Steris Plc SHS USD G8473T100 1,348 8,788 SH   SOLE NONE 3,145 0 5,643
Target Corp COM 87612E106 312 2,604 SH   SOLE NONE 0 0 2,604
Teladoc Health Inc. COM 87918A105 2,407 12,615 SH   SOLE NONE 5,850 0 6,765
Teledyne Inc COM 879360105 1,121 3,605 SH   SOLE NONE 1,120 0 2,485
Teleflex Incorporated COM 879369106 2,279 6,260 SH   SOLE NONE 2,585 0 3,675
Teradyne COM 880770102 2,244 26,555 SH   SOLE NONE 15,350 0 11,205
Trade Web Markets, Inc. CL A 892672106 1,038 17,856 SH   SOLE NONE 8,900 0 8,956
Tyler Technologies Inc COM 902252105 2,556 7,369 SH   SOLE NONE 2,680 0 4,689
Unilever Plc SPON ADR NEW 904767704 362 6,588 SH   SOLE NONE 0 0 6,588
V. F. Corporation COM 918204108 260 4,267 SH   SOLE NONE 0 0 4,267
Verizon Communications COM 92343V104 681 12,347 SH   SOLE NONE 0 0 12,347
Visa Inc. COM CL A 92826C839 3,238 16,765 SH   SOLE NONE 4,397 0 12,368
West Pharmaceuticals Services COM 955306105 3,857 16,979 SH   SOLE NONE 6,220 0 10,759
Zoetis Inc. CL A 98978V103 3,133 22,865 SH   SOLE NONE 8,920 0 13,945