<PAGE> PAGE 1
000 A000000 11/30/1999
000 C000000 0001047918
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 6.1
000 J000000 A
001 A000000 MSDW COMPETITIVE EDGE FUND BEST IDEAS PORT.
001 B000000 811-8455
001 C000000 2123922550
002 A000000 2 WORLD TRADE CENTER
002 B000000 NEW YORK
002 C000000 NY
002 D010000 10048
003 000000 N
004 000000 N
005 000000 N
006 000000 N
007 A000000 N
007 B000000 0
007 C010100 1
007 C020100 "BEST IDEAS" PORTFOLIO
007 C030100 N
007 C010200 2
007 C010300 3
007 C010400 4
007 C010500 5
007 C010600 6
007 C010700 7
007 C010800 8
007 C010900 9
007 C011000 10
008 A000001 MORGAN STANLEY DEAN WITTER ADVISORS INC.
008 B000001 A
008 C000001 801-42061
008 D010001 NEW YORK
008 D020001 NY
008 D030001 10048
011 A000001 MORGAN STANLEY DEAN WITTER DISTRIBUTORS INC.
011 B000001 8-45262
011 C010001 NEW YORK
011 C020001 NY
011 C030001 10048
012 A000001 MORGAN STANLEY DEAN WITTER TRUST FSB
012 B000001 84-1785
012 C010001 JERSEY CITY
012 C020001 NJ
012 C030001 07311
013 A000001 PRICEWATERHOUSECOOPERS LLP
<PAGE> PAGE 2
013 B010001 NEW YORK
013 B020001 NY
013 B030001 10036
014 A000001 DEAN WITTER REYNOLDS INC.
014 B000001 8-14172
014 A000002 MORGAN STANLEY & CO. INCORPORATED
014 B000002 8-15869
015 A000001 THE BANK OF NEW YORK
015 B000001 C
015 C010001 NEW YORK
015 C020001 NY
015 C030001 10007
015 E010001 X
018 000000 Y
019 A000000 Y
019 B000000 128
019 C000000 MSDW-FUNDS
020 A000001 MORGAN STANLEY & CO. INCORPORATED
020 B000001 13-2655998
020 C000001 665
020 A000002 DEUTSCHE BANK SECURITIES CORP
020 B000002 13-2730828
020 C000002 23
020 A000003 SALOMON BROTHERS INC.
020 B000003 13-3082694
020 C000003 10
020 A000004 BANK OF NEW YORK (THE)
020 B000004 13-5160382
020 C000004 2
020 A000005 LEHMAN BROTHERS INC.
020 B000005 13-2518466
020 C000005 1
020 C000006 0
020 C000007 0
020 C000008 0
020 C000009 0
020 C000010 0
021 000000 701
022 A000001 BANK OF AMERICA SECURITIES LLC.
022 B000001 56-2058405
022 C000001 1564203
022 D000001 0
022 A000002 MERRILL LYNCH, PIERCE, FENNER & SMITH INC.
022 B000002 13-5674085
022 C000002 1275953
022 D000002 0
022 A000003 BANK OF NEW YORK (THE)
022 B000003 13-5160382
022 C000003 198067
022 D000003 0
022 A000004 GOLDMAN, SACHS & CO.
<PAGE> PAGE 3
022 B000004 13-5108880
022 C000004 165670
022 D000004 0
022 A000005 LEHMAN BROTHERS INC
022 B000005 13-2518466
022 C000005 3509
022 D000005 25619
022 A000006 PAINEWEBBER INC.
022 B000006 13-2638166
022 C000006 0
022 D000006 24746
022 A000007 SALOMON SMITH BARNEY INC.
022 B000007 13-1912900
022 C000007 7047
022 D000007 0
022 A000008 MORGAN (J.P.) SECURITIES INC
022 B000008 13-3224016
022 C000008 3809
022 D000008 0
022 A000009 PRUDENTIAL SECURITIES INC.
022 B000009 22-2347336
022 C000009 1308
022 D000009 0
022 C000010 0
022 D000010 0
023 C000000 3219567
023 D000000 50366
024 000000 Y
025 A000001 BANK OF NEW YORK (THE)
025 B000001 13-5160382
025 C000001 E
025 D000001 47850
025 A000002 BANK OF NEW YORK (THE)
025 B000002 13-5160382
025 C000002 D
025 D000002 719
025 D000003 0
025 D000004 0
025 D000005 0
025 D000006 0
025 D000007 0
025 D000008 0
026 A000000 N
026 B000000 Y
026 C000000 N
026 D000000 Y
026 E000000 N
026 F000000 N
026 G010000 N
026 G020000 N
026 H000000 N
<PAGE> PAGE 4
027 000000 Y
028 A010000 8659
028 A020000 0
028 A030000 0
028 A040000 36249
028 B010000 11499
028 B020000 0
028 B030000 0
028 B040000 42043
028 C010000 9868
028 C020000 0
028 C030000 0
028 C040000 33090
028 D010000 12015
028 D020000 0
028 D030000 0
028 D040000 30069
028 E010000 17435
028 E020000 0
028 E030000 0
028 E040000 30003
028 F010000 15114
028 F020000 0
028 F030000 0
028 F040000 36250
028 G010000 74590
028 G020000 0
028 G030000 0
028 G040000 207704
028 H000000 71617
029 000000 Y
030 A000000 40
030 B000000 5.25
030 C000000 0.00
031 A000000 0
031 B000000 1
032 000000 0
033 000000 41
034 000000 Y
035 000000 2673
036 A000000 N
036 B000000 0
037 000000 N
038 000000 0
039 000000 N
040 000000 Y
041 000000 Y
042 A000000 0
042 B000000 0
042 C000000 100
042 D000000 0
<PAGE> PAGE 5
042 E000000 0
042 F000000 0
042 G000000 0
042 H000000 0
043 000000 9105
044 000000 0
045 000000 Y
046 000000 N
047 000000 Y
048 000000 0.000
048 A010000 1500000
048 A020000 0.650
048 B010000 0
048 B020000 0.000
048 C010000 0
048 C020000 0.000
048 D010000 0
048 D020000 0.000
048 E010000 0
048 E020000 0.000
048 F010000 0
048 F020000 0.000
048 G010000 0
048 G020000 0.000
048 H010000 0
048 H020000 0.000
048 I010000 0
048 I020000 0.000
048 J010000 0
048 J020000 0.000
048 K010000 1500000
048 K020000 0.625
049 000000 N
050 000000 N
051 000000 N
052 000000 N
053 A000000 N
054 A000000 Y
054 B000000 Y
054 C000000 N
054 D000000 N
054 E000000 N
054 F000000 N
054 G000000 Y
054 H000000 Y
054 I000000 N
054 J000000 Y
054 K000000 N
054 L000000 Y
054 M000000 Y
054 N000000 N
<PAGE> PAGE 6
054 O000000 Y
055 A000000 N
055 B000000 N
056 000000 Y
057 000000 N
058 A000000 N
059 000000 Y
060 A000000 Y
060 B000000 Y
061 000000 1000
062 A000000 N
062 B000000 0.0
062 C000000 0.0
062 D000000 0.0
062 E000000 0.0
062 F000000 0.0
062 G000000 0.0
062 H000000 0.0
062 I000000 0.0
062 J000000 0.0
062 K000000 0.0
062 L000000 0.0
062 M000000 0.0
062 N000000 0.0
062 O000000 0.0
062 P000000 0.0
062 Q000000 0.0
062 R000000 0.0
063 A000000 0
063 B000000 0.0
066 A000000 Y
066 B000000 N
066 C000000 N
066 D000000 Y
066 E000000 N
066 F000000 N
066 G000000 N
067 000000 N
068 A000000 N
068 B000000 N
069 000000 N
070 A010000 Y
070 A020000 Y
070 B010000 Y
070 B020000 N
070 C010000 Y
070 C020000 N
070 D010000 Y
070 D020000 N
070 E010000 Y
070 E020000 N
<PAGE> PAGE 7
070 F010000 Y
070 F020000 N
070 G010000 Y
070 G020000 N
070 H010000 Y
070 H020000 N
070 I010000 N
070 I020000 N
070 J010000 Y
070 J020000 N
070 K010000 Y
070 K020000 N
070 L010000 Y
070 L020000 Y
070 M010000 Y
070 M020000 Y
070 N010000 Y
070 N020000 N
070 O010000 N
070 O020000 N
070 P010000 Y
070 P020000 N
070 Q010000 N
070 Q020000 N
070 R010000 N
070 R020000 N
071 A000000 313090
071 B000000 440593
071 C000000 1876320
071 D000000 17
072 A000000 6
072 B000000 621
072 C000000 7842
072 D000000 0
072 E000000 0
072 F000000 6166
072 G000000 0
072 H000000 0
072 I000000 1259
072 J000000 229
072 K000000 0
072 L000000 111
072 M000000 6
072 N000000 122
072 O000000 0
072 P000000 0
072 Q000000 0
072 R000000 20
072 S000000 20
072 T000000 9105
072 U000000 14
<PAGE> PAGE 8
072 V000000 0
072 W000000 13
072 X000000 17066
072 Y000000 0
072 Z000000 -8603
072AA000000 83945
072BB000000 50073
072CC010000 196470
072CC020000 0
072DD010000 0
072DD020000 0
072EE000000 0
073 A010000 0.0000
073 A020000 0.0000
073 B000000 0.0000
073 C000000 0.0000
074 A000000 0
074 B000000 719
074 C000000 11000
074 D000000 0
074 E000000 43936
074 F000000 1893368
074 G000000 0
074 H000000 0
074 I000000 0
074 J000000 0
074 K000000 0
074 L000000 4282
074 M000000 204
074 N000000 1953509
074 O000000 0
074 P000000 2790
074 Q000000 0
074 R010000 0
074 R020000 0
074 R030000 0
074 R040000 3421
074 S000000 0
074 T000000 1947298
074 U010000 149069
074 U020000 12024
074 V010000 0.00
074 V020000 0.00
074 W000000 0.0000
074 X000000 172436
074 Y000000 0
075 A000000 0
075 B000000 1913154
076 000000 0.00
077 A000000 N
078 000000 N
<PAGE> PAGE 9
080 C000000 0
081 B000000 0
082 B000000 0
083 B000000 0
084 B000000 0
086 A010000 0
086 A020000 0
086 B010000 0
086 B020000 0
086 C010000 0
086 C020000 0
086 D010000 0
086 D020000 0
086 E010000 0
086 E020000 0
086 F010000 0
086 F020000 0
SIGNATURE BARRY FINK
TITLE VICE PRESIDENT
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Morgan Stanley Dean Witter Competitive Edge Fund
Class A
</LEGEND>
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-END> NOV-30-1999
<INVESTMENTS-AT-COST> 1,550,064,697
<INVESTMENTS-AT-VALUE> 1,949,023,064
<RECEIVABLES> 4,282,443
<ASSETS-OTHER> 203,752
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,953,509,259
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (6,211,134)
<TOTAL-LIABILITIES> (6,211,134)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,598,591,999
<SHARES-COMMON-STOCK> 7,794,098
<SHARES-COMMON-PRIOR> 9,110,813
<ACCUMULATED-NII-CURRENT> (8,656,703)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (41,541,739)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 398,904,568
<NET-ASSETS> 95,252,481
<DIVIDEND-INCOME> 7,841,790
<INTEREST-INCOME> 620,944
<OTHER-INCOME> 0
<EXPENSES-NET> (17,065,675)
<NET-INVESTMENT-INCOME> (8,602,941)
<REALIZED-GAINS-CURRENT> 33,871,860
<APPREC-INCREASE-CURRENT> 196,469,895
<NET-CHANGE-FROM-OPS> 221,738,814
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 185,813
<NUMBER-OF-SHARES-REDEEMED> (1,502,528)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 88,625,318
<ACCUMULATED-NII-PRIOR> (53,762)
<ACCUMULATED-GAINS-PRIOR> (75,413,599)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (6,166,105)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (17,065,675)
<AVERAGE-NET-ASSETS> 95,523,955
<PER-SHARE-NAV-BEGIN> 10.84
<PER-SHARE-NII> (0.01)
<PER-SHARE-GAIN-APPREC> 1.39
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 12.22
<EXPENSE-RATIO> 1.07
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Morgan Stanley Dean Witter Competitive Edge Fund
Class B
</LEGEND>
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-END> NOV-30-1999
<INVESTMENTS-AT-COST> 1,550,064,697
<INVESTMENTS-AT-VALUE> 1,949,023,064
<RECEIVABLES> 4,282,443
<ASSETS-OTHER> 203,752
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,953,509,259
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (6,211,134)
<TOTAL-LIABILITIES> (6,211,134)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,598,591,999
<SHARES-COMMON-STOCK> 141,274,587
<SHARES-COMMON-PRIOR> 150,068,555
<ACCUMULATED-NII-CURRENT> (8,656,703)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (41,541,739)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 398,904,568
<NET-ASSETS> 1,706,348,506
<DIVIDEND-INCOME> 7,841,790
<INTEREST-INCOME> 620,944
<OTHER-INCOME> 0
<EXPENSES-NET> (17,065,675)
<NET-INVESTMENT-INCOME> (8,602,941)
<REALIZED-GAINS-CURRENT> 33,871,860
<APPREC-INCREASE-CURRENT> 196,469,895
<NET-CHANGE-FROM-OPS> 221,738,814
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 5,536,679
<NUMBER-OF-SHARES-REDEEMED> (14,330,647)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 88,625,318
<ACCUMULATED-NII-PRIOR> (53,762)
<ACCUMULATED-GAINS-PRIOR> (75,413,599)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (6,166,105)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (17,065,675)
<AVERAGE-NET-ASSETS> 1,673,457,918
<PER-SHARE-NAV-BEGIN> 10.76
<PER-SHARE-NII> (0.05)
<PER-SHARE-GAIN-APPREC> 1.37
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 12.08
<EXPENSE-RATIO> 1.83
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Morgan Stanley Dean Witter Competitive Edge Fund
Class C
</LEGEND>
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-END> NOV-30-1999
<INVESTMENTS-AT-COST> 1,550,064,697
<INVESTMENTS-AT-VALUE> 1,949,023,064
<RECEIVABLES> 4,282,443
<ASSETS-OTHER> 203,752
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,953,509,259
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (6,211,134)
<TOTAL-LIABILITIES> (6,211,134)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,598,591,999
<SHARES-COMMON-STOCK> 11,667,746
<SHARES-COMMON-PRIOR> 13,175,973
<ACCUMULATED-NII-CURRENT> (8,656,703)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (41,541,739)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 398,904,568
<NET-ASSETS> 141,332,575
<DIVIDEND-INCOME> 7,841,790
<INTEREST-INCOME> 620,944
<OTHER-INCOME> 0
<EXPENSES-NET> (17,065,675)
<NET-INVESTMENT-INCOME> (8,602,941)
<REALIZED-GAINS-CURRENT> 33,871,860
<APPREC-INCREASE-CURRENT> 196,469,895
<NET-CHANGE-FROM-OPS> 221,738,814
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 471,726
<NUMBER-OF-SHARES-REDEEMED> (1,979,953)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 88,625,318
<ACCUMULATED-NII-PRIOR> (53,762)
<ACCUMULATED-GAINS-PRIOR> (75,413,599)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (6,166,105)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (17,065,675)
<AVERAGE-NET-ASSETS> 141,929,782
<PER-SHARE-NAV-BEGIN> 10.78
<PER-SHARE-NII> (0.05)
<PER-SHARE-GAIN-APPREC> 1.38
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 12.11
<EXPENSE-RATIO> 1.71
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Morgan Stanley Dean Witter Competitive Edge Fund
Class D
</LEGEND>
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-END> NOV-30-1999
<INVESTMENTS-AT-COST> 1,550,064,697
<INVESTMENTS-AT-VALUE> 1,949,023,064
<RECEIVABLES> 4,282,443
<ASSETS-OTHER> 203,752
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,953,509,259
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (6,211,134)
<TOTAL-LIABILITIES> (6,211,134)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,598,591,999
<SHARES-COMMON-STOCK> 356,036
<SHARES-COMMON-PRIOR> 332,322
<ACCUMULATED-NII-CURRENT> (8,656,703)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (41,541,739)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 398,904,568
<NET-ASSETS> 4,364,563
<DIVIDEND-INCOME> 7,841,790
<INTEREST-INCOME> 620,944
<OTHER-INCOME> 0
<EXPENSES-NET> (17,065,675)
<NET-INVESTMENT-INCOME> (8,602,941)
<REALIZED-GAINS-CURRENT> 33,871,860
<APPREC-INCREASE-CURRENT> 196,469,895
<NET-CHANGE-FROM-OPS> 221,738,814
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 252,907
<NUMBER-OF-SHARES-REDEEMED> (229,193)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 88,625,318
<ACCUMULATED-NII-PRIOR> (53,762)
<ACCUMULATED-GAINS-PRIOR> (75,413,599)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (6,166,105)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (17,065,675)
<AVERAGE-NET-ASSETS> 2,241,887
<PER-SHARE-NAV-BEGIN> 10.87
<PER-SHARE-NII> 0.00
<PER-SHARE-GAIN-APPREC> 1.39
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 12.26
<EXPENSE-RATIO> 0.83
</TABLE>